Add support for diagnosticSettings

[nishant221]

Closes #4248

What this PR does / why we need it:
Add support for a new resource DiagnosticSetting

Special notes for your reviewer:

How does this PR make you feel:
Excited :)

If applicable:

• this PR contains documentation
• this PR contains tests
• this PR contains YAML Samples

[theunrepentantgeek]

This is really solid, good job. I made a few comments to improve your test, and you need to make a recording of your sample, but other than that it's very nearly complete.

[theunrepentantgeek]

/ok-to-test sha=e7174dd

[theunrepentantgeek]

/ok-to-test sha=e7174dd

[theunrepentantgeek]

CI is failing because you're missing an update to one file - v2/api/insights/versions_matrix.md.

Once that's included, we can run the full test suite and look at merging this contribution. Thanks!

Spoiler alert: I ran the full test suite locally, and it passed. 😉

[nishant221]

@theunrepentantgeek Thanks for the valuable feedbacks. Added the missing updates to the file - v2/api/insights/versions_matrix.md . Kindly have a re-look.
Thanks

[theunrepentantgeek]

/ok-to-test sha=2be47b4

[matthchr]

/ok-to-test sha=27a974c

[theunrepentantgeek]

A couple of markdown files are generating with different content, looks like the generator is now picking up on the sample and is including links in the index files. I've confirmed this locally:

$ git status
On branch feature/diagnosticsetting
Changes not staged for commit:
  (use "git add <file>..." to update what will be committed)
  (use "git restore <file>..." to discard changes in working directory)
        modified:   docs/hugo/content/reference/_index.md
        modified:   docs/hugo/content/reference/insights/_index.md

Run task controller:generate-types to regenerate them. Once CI is clean, we'll merge this.

[nishant221]

Ran the above mentioned command and committed the changes 0f45678

[matthchr]

/ok-to-test sha=0f45678

[theunrepentantgeek]

Thanks @nishant221, great contribution.