Otherwise, this may pick the wrong arch like s390x, if a such a podman
container was most recently used.
See also the CI_IMAGE_PLATFORM setting in the "other" CI, which does the
same.
On merges to master we set LINT_CI_SANITY_CHECK_COMMIT_SIG (when
"GITHUB_REPOSITORY == bitcoin/bitcoin") which runs verify-commits.py.
This requires write access to the .git directory.
Make the mounted .git directory writable.
This is currently not run on PR branches or locally which caused a miss
during review.
Add a ci/lint.py script to run the linter both locally or inside the CI
(replacing .github/ci-lint-exec.py) which supports running from a
worktree.
Determines whether we are in a worktree, and mounts the real `.git`
directory as a read-only volume if we are.
