Document Updating Gitaly calls

Why

Summary

When reviewing code that contains changes to calls to Gitaly, we want to check if the gitaly gem was updated to support changes.

Details

This came up while reviewing an MR where I asked this question about how to review MRs in our domain that include a change to a call to Gitaly (new arguments for an existing method in this case). I got this answer which was very helpful.

What

I'm not sure if this is really team specific or belongs anywhere around the team handbook page, but documenting this somewhere seems helpful.

• see if this kind of documentation already exists
• if it does, make sure it's easily discoverable for our team since we're likely to interact with this kind of MR
• if not, figure out best place to document something like this and add it