Update TW Lead release process for clarity

Why is this change being made?

Upon review, the release process includes several responsibilities for the TW Lead that in many cases will be handled by TWs as they submit release post items. While things can change, and we need a final set of eyes on things, I'd like to ensure that the TW Lead is mostly providing a quick, final review to ensure no problems have snuck through or were accidentally introduced.

This MR attempts to distill the basic requirements for the TW Lead to ensure that the most value is being provided with the appropriate amount of effort. The MR also moves formatting information for the release posts into their structural sections and out of the TW Lead section to help with discoverability of this formatting information.

There may be some follow-on efficiencies we can identify for the bug and feature improvement MR processes, but this is an MVC to attempt to begin to implement straightforward changes for the TW Lead to make the process easier to implement.

Author Checklist

• Provided a concise title for the MR
• Added a description to this MR explaining the reasons for the proposed change, per say-why-not-just-what
• Assign this change to the correct DRI
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