fix(release): refresh the Alpine index snapshot after upstream republish

Alpine republished both v3.23 main indexes this morning, so every
guest-image build failed its immutable index digest check. Refresh the
two changed APKINDEX pins from the live repository (both community
indexes are unchanged) and update the reviewed capturedAt in check.mjs
and the release test, per the security-refresh ritual.

Co-authored-by: Cursor <cursoragent@cursor.com>