Move release meta-data into footer on Releases page

What does this MR do?

Moves the commit SHA, tag, and release author/time into the footer area of each release block on the Releases page.

This is the first half of #31289 (closed). This change is not intended to be released without the second half (!19448 (merged)), which will remove the duplicated info from the top of the release block's content section.

Feature flag

This feature is hidden behind a release_issue_summary feature flag which is disabled by default. The feature flag will be enabled when both this MR and !19448 (merged) have been merged.

Screenshots

Responsive behavior