pr-overlap and area-labels walked every open PR on each run, spending the
1000 requests/hour that GITHUB_TOKEN gets per repository and starving the
other workflows (HTTP 403 'rate limit exceeded for installation').
pr-overlap keeps a hash of each report in actions/cache and only reads the
comments of PRs whose report changed. area-labels keeps head SHA plus the
labeler.yml blob per PR and labels only the changed ones, at most 40 per
run. conflict-label gets a concurrency group so pushes in a row don't stack
full passes.
Adrià Franch