Add explicit save / revert buttons in search & ingest forms

[ohltyler]

Description

This PR reverts the autosave functionality due to its ambiguity on when cluster resources are updated. To handle saving, this adds an explicit save button, and corresponding undo, to revert to the last saved state. Buttons are enabled/disabled based on the form state. Under the hood, when users click save, it runs the update workflow API with reprovision=false. Only the config is saved, but not the underlying workflow template or any associated resources. For full updates, users still have the ingest/search buttons. Updated text to more explicitly state what is happening when those are executed, which is actually building out the resources and running ingest/search. When users click the revert button, the form and transient UI config is reverted to the saved/indexed config.

Details on the different form states:

• all general form state is all handled by formik to detect value changes, when values are touched, etc.
• when ingest/search processors are added/removed, rather than updating the form, we have to re-create the form and updated form schema. This is because we generate the form based on metadata in the UI config (the config field types, defaults, etc.), and can't go vice-versa. Note this is why we pass the setUiConfig param to components, so it can be triggered on these particular actions. Because we can't listen on formik value changes for this part, we need standalone hooks to listen on when the current uiConfig has updated.

Implementation details:

• adds unsavedIngestProcessors/unsavedSearchProcessors flags to persist when there are form changes related to adding/removing ingest/search processors
• adds hooks to listen when the uiConfig has updated, and detect processor config changes to set unsavedIngestProcessors/unsavedSearchProcessors
• refactors the autosave logic to have a single updateWorkflowUiConfig() fn to update the UI config only, without any template or resource updates. Used in the new Save button
• adds revert/save buttons for both ingest/search conditions

Demo video, showing the new buttons functionality for ingest/search:

screen-capture.16.webm

Check List

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