Update release cheat sheet

[lbernick]

Changes

This commit updates the release cheat sheet with some things I ran into
when doing the most recent release.

/kind documentation

Submitter Checklist

As the author of this PR, please check off the items in this checklist:

• Has Docs included if any changes are user facing
• n/a Has Tests included if any functionality added or changed
• Follows the commit message standard
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• Has a kind label. You can add one by adding a comment on this PR that contains /kind <type>. Valid types are bug, cleanup, design, documentation, feature, flake, misc, question, tep
• n/a Release notes block below has been updated with any user facing changes (API changes, bug fixes, changes requiring upgrade notices or deprecation warnings)
• n/a Release notes contains the string "action required" if the change requires additional action from users switching to the new release

Release Notes

NONE

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[dibyom]

/lgtm