The components repo and framework repository follow the same patch
branch concept. We should be able to share a script for determining
these merge branches.
Additonally the logic has been improved compared to the old merge script because
we no longer consult `git ls-remote` unless really needed. Currently,
`git ls-remote` is always consulted, even though not necessarily needed.
This can slow down the merge script and the caretaker process when a
couple of PRs are merged (personally saw around ~4 seconds per merge).
Additionally, the new logic is more strict and will ensure (in most
cases) that no wrong patch/minor branch is determined. Previously,
the script just used the lexicographically greatest patch branch.
This _could_ be wrong when a new patch branch has been created too
early, or by accident.
PR Close#37217
Integrates the merge script into the `ng-dev` CLI. The goal is that
caretakers can run the same command across repositories to merge a pull
request. The command is as followed: `yarn ng-dev pr merge <number>`.
PR Close#37138