fix(MeshTimeout): remove if-condition that prevents plugin from running when there are no policies

[lobkovilya]

Motivation

This if-condition at the beginning of the plugin

if len(policies.ToRules.Rules) == 0 && len(policies.FromRules.Rules) == 0 && len(policies.GatewayRules.ToRules.ByListener) == 0 && len(policies.ToRules.ResourceRules) == 0 {
    return nil
}

causes inconsistent default values. For example, the default outbound timeouts should be the same regardless of the presence of MeshTimeout policies with from.

Implementation information

Depends on #12766

Supporting documentation

Fix #12649

Changelog: feat(MeshTimeout): add possibility to configure inbound using rules api

[github-actions]

Reviewer Checklist

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• Is the PR title satisfactory? Is this part of a larger feature and should be grouped using > Changelog?
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• This will not break child repos: it doesn't hardcode values (.e.g "kumahq" as an image registry)
• IPv6 is taken into account (.e.g: no string concatenation of host port)
• Tests (Unit test, E2E tests, manual test on universal and k8s)
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[Automaat]

Looking at this pr, it looks like we were missing default timeouts?

[lobkovilya]

Looking at this pr, it looks like we were missing default timeouts?

Most of the time they're the same as Envoy's defaults. But sometimes they're not and bad case is explained in the issue #12649