checkout, cq_deps: Resolve deps in commit messages

Resolve dependency references in commit messages like below, and only in
the last "paragraph". "ignore:" is added because otherwise CQ won't
process this CL.

ignore:Cq-Depend: gerritname:1, commas-supported:2,spaces-not-required:3
ignore:Cq-Depend: name:4
ignore:Cq-Depend: name:5,,,,extra-commas-ignored:6,,,,

Compare http://go/bbid/8866545454308933312 and led run below for
pwrev/17461. Both builds fail for unrelated reasons, but the led build
applies two changes instead of just one.

$ led get-build 8866545454308933312 | led edit-recipe-bundle | led launch
LUCI UI: https://ci.chromium.org/swarming/task/4f3b6ebae9aabf10?server=chromium-swarm.appspot.com

Change-Id: I493ff86e1cc09fb4221a9faa41786bfbb1441461
Bug: 233
Reviewed-on: https://pigweed-review.googlesource.com/c/infra/recipes/+/20260
Commit-Queue: Rob Mohr <mohrr@google.com>
Reviewed-by: Marc-Antoine Ruel <maruel@google.com>
Reviewed-by: Oliver Newman <olivernewman@google.com>
47 files changed
tree: 032d290317fa9819a79290c577c548c733cb26da
  1. infra/
  2. recipe_modules/
  3. recipes/
  4. .gitignore
  5. .style.yapf
  6. recipes.py