Tag v0.42.0 - GitSync clone depth

GitSync gains a `depth` keyword argument so callers can clone at an
arbitrary shallow depth (`git clone --depth N`), not just a single
commit. Passing `git_shallow` or `tls_verify` to the GitSync
constructor now sets the attribute instead of raising AttributeError
on the next sync (a regression dating back to v0.4.4).

See CHANGES for the full release notes.

Tag v0.41.0 - pytest plugin renamings

Tag v0.40.0

Tag v0.39.0 (`SyncResult`, bug fixes)

Tag v0.38.6 (test harness tweak)

Tag v0.38.5 (test harness tweak)

Tag v0.38.4 (test harness tweak, attempt 2)

Tag v0.38.3 (test harness tweak for git)

Tag v0.38.2 (PyPI Trusted Publisher)

Tag v0.38.1 (doc fixes)