Add bumpmatrix and codegen automation commands

[miguelgrinberg]

This change adds implementations of the bumpmatrix and codegen commands to the .github/make.sh automation script.

[miguelgrinberg]

The failures are caused by a YAML test that uses a new endpoint that is currently not available in the client. Once we have code generation automation in place we'll be able to make incremental updates to the client as the spec evolves.

[miguelgrinberg]

Haven't got reviews on this in a few days, so I'm going to go ahead and merge anyway, given that this is adding new commands to make.sh without modifying any of the existing ones. This is going to allow me to start testing the automationc cron jobs that run on Mondays.

[github-actions]

The backport to 9.2 failed:

The process '/usr/bin/git' failed with exit code 128

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add .worktrees/backport-9.2 9.2
# Navigate to the new working tree
cd .worktrees/backport-9.2
# Create a new branch
git switch --create backport-1478-to-9.2
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 431e902e7fa50ffeac09d7e505186620bab5290c
# Push it to GitHub
git push --set-upstream origin backport-1478-to-9.2
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-9.2

Then, create a pull request where the base branch is 9.2 and the compare/head branch is backport-1478-to-9.2.