v2.1 release checklist

[jescalada]

These are the PRs that didn't make it to the v2.0 release outlined in #1368. Feel free to expand this list with any pressing features/bugfixes for 2.1! Any issues left over from #1368 will be added here to speed up the 2.0 release.

• feat(ssh): Add SSH agent forwarding #1332
  • Implements SSH + SSH agent forwarding
  • Currently awaiting external review (contributed by G-Research)
• feat: implement hybrid cache architecture #1246 Awaiting CI fix
• feat: Add Annotated Tag Push Support #1139 Awaiting merge conflict fix and external review

[kriswest]

I'd like to discuss #1246 again, it's very likely to conflict with a solution for #1386 (PR to fix is awaiting egress review). I think that should go first (in v2.0 as its a current bug), while we review #1246 as a far more complex addition. However, I am happy to see the use of a mutex isolating use of the cache!