Doc role handbook clean up

[annajung]

What type of PR is this:

/kind documentation
/kind cleanup

What this PR does / why we need it:

• Add templates that can be used to communicate docs deadline to enhancement/docs PR owners (Please look at this commit to see which content were changed: bf3ac59)
• Extract out the release timeline section into its own file to help with readability (removes use of h5 which is smaller than a regular text!)

Which issue(s) this PR fixes:

None

Special notes for your reviewer:

/assign @savitharaghunathan @jimangel

[jimangel]

There's a lot to be desired in the release timeline and I think we could clean up some of the meta "Read the release timeline" also within the release timeline, but overall this PR improves readability.

I would love to see the timeline cleaned up / stripped down to essentials for success.

Thanks @annajung for kicking off this clean-up!
/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: annajung, jimangel

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• release-team/role-handbooks/docs/OWNERS [annajung]

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