📖 Add docs for CD-ROM and ISO VM deployment workflow

[dilyar85]

What does this PR do, and why is it needed?

This PR adds the long-overdue docs for the vm.spec.cdrom field introduced in the v1alpha3 API, as well as a tutorial page for importing ISO images from URL, deploying VM from ISO, and configuring guest OS installation using web console.

Which issue(s) is/are addressed by this PR?

Fixes N/A.

Are there any special notes for your reviewer:

None.

Please add a release note if necessary:

Add docs for CD-ROM and ISO VM deployment workflow.

---

📚 Documentation preview 📚: https://vm-operator--843.org.readthedocs.build/en/843/

[akutz]

Approved with some notes if you want to tackle them now or later. Thanks @dilyar85 !

[github-actions]

Package	Line Rate	Health
github.com/vmware-tanzu/vm-operator/controllers/contentlibrary/clustercontentlibraryitem	82%	➖
github.com/vmware-tanzu/vm-operator/controllers/contentlibrary/contentlibraryitem	86%	➖
github.com/vmware-tanzu/vm-operator/controllers/contentlibrary/utils	97%	✔
github.com/vmware-tanzu/vm-operator/controllers/infra/capability/configmap	86%	➖
github.com/vmware-tanzu/vm-operator/controllers/infra/capability/crd	93%	✔
github.com/vmware-tanzu/vm-operator/controllers/infra/configmap	71%	❌
github.com/vmware-tanzu/vm-operator/controllers/infra/node	77%	❌
github.com/vmware-tanzu/vm-operator/controllers/infra/secret	77%	❌
github.com/vmware-tanzu/vm-operator/controllers/infra/validatingwebhookconfiguration	85%	➖
github.com/vmware-tanzu/vm-operator/controllers/infra/zone	76%	❌
github.com/vmware-tanzu/vm-operator/controllers/storageclass	95%	✔
github.com/vmware-tanzu/vm-operator/controllers/storagepolicyquota	97%	✔
github.com/vmware-tanzu/vm-operator/controllers/util/encoding	73%	❌
github.com/vmware-tanzu/vm-operator/controllers/virtualmachine/storagepolicyusage	99%	✔
github.com/vmware-tanzu/vm-operator/controllers/virtualmachine/virtualmachine	84%	➖
github.com/vmware-tanzu/vm-operator/controllers/virtualmachine/volume	87%	➖
github.com/vmware-tanzu/vm-operator/controllers/virtualmachineclass	75%	❌
github.com/vmware-tanzu/vm-operator/controllers/virtualmachinepublishrequest	81%	➖
github.com/vmware-tanzu/vm-operator/controllers/virtualmachinereplicaset	67%	❌
github.com/vmware-tanzu/vm-operator/controllers/virtualmachineservice	83%	➖
github.com/vmware-tanzu/vm-operator/controllers/virtualmachineservice/providers	92%	✔
github.com/vmware-tanzu/vm-operator/controllers/virtualmachinesetresourcepolicy	80%	➖
github.com/vmware-tanzu/vm-operator/controllers/virtualmachinewebconsolerequest	72%	❌
github.com/vmware-tanzu/vm-operator/controllers/virtualmachinewebconsolerequest/v1alpha1	72%	❌
github.com/vmware-tanzu/vm-operator/controllers/virtualmachinewebconsolerequest/v1alpha1/conditions	88%	➖
github.com/vmware-tanzu/vm-operator/controllers/virtualmachinewebconsolerequest/v1alpha1/patch	78%	❌
github.com/vmware-tanzu/vm-operator/pkg/bitmask	100%	✔
github.com/vmware-tanzu/vm-operator/pkg/builder	95%	✔
github.com/vmware-tanzu/vm-operator/pkg/conditions	88%	➖
github.com/vmware-tanzu/vm-operator/pkg/config	100%	✔
github.com/vmware-tanzu/vm-operator/pkg/config/capabilities	100%	✔
github.com/vmware-tanzu/vm-operator/pkg/config/env	100%	✔
github.com/vmware-tanzu/vm-operator/pkg/context/generic	100%	✔
github.com/vmware-tanzu/vm-operator/pkg/context/operation	100%	✔
github.com/vmware-tanzu/vm-operator/pkg/patch	78%	❌
github.com/vmware-tanzu/vm-operator/pkg/prober	91%	✔
github.com/vmware-tanzu/vm-operator/pkg/prober/probe	90%	✔
github.com/vmware-tanzu/vm-operator/pkg/prober/worker	77%	❌
github.com/vmware-tanzu/vm-operator/pkg/providers/vsphere	72%	❌
github.com/vmware-tanzu/vm-operator/pkg/providers/vsphere/client	80%	➖
github.com/vmware-tanzu/vm-operator/pkg/providers/vsphere/clustermodules	71%	❌
github.com/vmware-tanzu/vm-operator/pkg/providers/vsphere/config	89%	✔
github.com/vmware-tanzu/vm-operator/pkg/providers/vsphere/contentlibrary	74%	❌
github.com/vmware-tanzu/vm-operator/pkg/providers/vsphere/credentials	100%	✔
github.com/vmware-tanzu/vm-operator/pkg/providers/vsphere/network	80%	➖
github.com/vmware-tanzu/vm-operator/pkg/providers/vsphere/placement	80%	➖
github.com/vmware-tanzu/vm-operator/pkg/providers/vsphere/session	71%	❌
github.com/vmware-tanzu/vm-operator/pkg/providers/vsphere/storage	44%	❌
github.com/vmware-tanzu/vm-operator/pkg/providers/vsphere/sysprep	100%	✔
github.com/vmware-tanzu/vm-operator/pkg/providers/vsphere/vcenter	81%	➖
github.com/vmware-tanzu/vm-operator/pkg/providers/vsphere/virtualmachine	84%	➖
github.com/vmware-tanzu/vm-operator/pkg/providers/vsphere/vmlifecycle	65%	❌
github.com/vmware-tanzu/vm-operator/pkg/record	87%	➖
github.com/vmware-tanzu/vm-operator/pkg/topology	91%	✔
github.com/vmware-tanzu/vm-operator/pkg/util	88%	➖
github.com/vmware-tanzu/vm-operator/pkg/util/cloudinit	89%	✔
github.com/vmware-tanzu/vm-operator/pkg/util/cloudinit/validate	91%	✔
github.com/vmware-tanzu/vm-operator/pkg/util/image	100%	✔
github.com/vmware-tanzu/vm-operator/pkg/util/kube	89%	➖
github.com/vmware-tanzu/vm-operator/pkg/util/kube/cource	100%	✔
github.com/vmware-tanzu/vm-operator/pkg/util/kube/internal	100%	✔
github.com/vmware-tanzu/vm-operator/pkg/util/kube/proxyaddr	73%	❌
github.com/vmware-tanzu/vm-operator/pkg/util/kube/spq	100%	✔
github.com/vmware-tanzu/vm-operator/pkg/util/netplan	100%	✔
github.com/vmware-tanzu/vm-operator/pkg/util/ovfcache	75%	❌
github.com/vmware-tanzu/vm-operator/pkg/util/ovfcache/internal	100%	✔
github.com/vmware-tanzu/vm-operator/pkg/util/paused	100%	✔
github.com/vmware-tanzu/vm-operator/pkg/util/ptr	100%	✔
github.com/vmware-tanzu/vm-operator/pkg/util/resize	97%	✔
github.com/vmware-tanzu/vm-operator/pkg/util/vmopv1	80%	➖
github.com/vmware-tanzu/vm-operator/pkg/util/vsphere/client	64%	❌
github.com/vmware-tanzu/vm-operator/pkg/util/vsphere/library	100%	✔
github.com/vmware-tanzu/vm-operator/pkg/util/vsphere/vm	79%	❌
github.com/vmware-tanzu/vm-operator/pkg/util/vsphere/watcher	87%	➖
github.com/vmware-tanzu/vm-operator/pkg/vmconfig	95%	✔
github.com/vmware-tanzu/vm-operator/pkg/vmconfig/crypto	98%	✔
github.com/vmware-tanzu/vm-operator/pkg/webconsolevalidation	100%	✔
github.com/vmware-tanzu/vm-operator/services/vm-watcher	92%	✔
github.com/vmware-tanzu/vm-operator/webhooks/common	100%	✔
github.com/vmware-tanzu/vm-operator/webhooks/persistentvolumeclaim/validation	95%	✔
github.com/vmware-tanzu/vm-operator/webhooks/unifiedstoragequota/validation	89%	✔
github.com/vmware-tanzu/vm-operator/webhooks/virtualmachine/mutation	87%	➖
github.com/vmware-tanzu/vm-operator/webhooks/virtualmachine/validation	95%	✔
github.com/vmware-tanzu/vm-operator/webhooks/virtualmachineclass/mutation	62%	❌
github.com/vmware-tanzu/vm-operator/webhooks/virtualmachineclass/validation	89%	➖
github.com/vmware-tanzu/vm-operator/webhooks/virtualmachinepublishrequest/validation	92%	✔
github.com/vmware-tanzu/vm-operator/webhooks/virtualmachinereplicaset/validation	90%	✔
github.com/vmware-tanzu/vm-operator/webhooks/virtualmachineservice/mutation	67%	❌
github.com/vmware-tanzu/vm-operator/webhooks/virtualmachineservice/validation	92%	✔
github.com/vmware-tanzu/vm-operator/webhooks/virtualmachinesetresourcepolicy/validation	89%	✔
github.com/vmware-tanzu/vm-operator/webhooks/virtualmachinewebconsolerequest/v1alpha1/validation	92%	✔
github.com/vmware-tanzu/vm-operator/webhooks/virtualmachinewebconsolerequest/validation	92%	✔
Summary	83% (10911 / 13225)	➖

Minimum allowed line rate is 79%