Fixes 15839: More accurate documentation about setting up Secret Manager in Azure

[Nemeczek]

Describe your changes:

Fixes 15839

It is possible to use Azure Key Vault as Secrets Manager but the docs needed few more pointers. If you don't want to add this all boring stuff about Manged Identities then the updates YAML snippets should be enough.

Type of change:

• Bug fix
• Improvement
• New feature
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation

Checklist:

• I have read the CONTRIBUTING document.
• My PR title is Fixes <issue-number>: <short explanation>
• I have commented on my code, particularly in hard-to-understand areas.
• For JSON Schema changes: I updated the migration scripts or explained why it is not needed.

[github-actions]

Hi there 👋 Thanks for your contribution!

The OpenMetadata team will review the PR shortly! Once it has been labeled as safe to test, the CI workflows
will start executing and we'll be able to make sure everything is working as expected.

Let us know if you need any help!

[pmbrull]

thanks @Nemeczek for the help