Run the in-repo Complement test suite in CI, even when the standard Complement suite fails. (#20161)

Supersedes: https://github.com/element-hq/synapse-private/pull/155

It would be useful to have the in-repo Complement suite give a status,
even when the normal suite fails (e.g. flakes).

---------

Signed-off-by: Olivier 'reivilibre <oliverw@matrix.org>
Co-authored-by: Andrew Morgan <1342360+anoadragon453@users.noreply.github.com>

.github/workflows/complement_tests.yml

@@ -160,6 +160,10 @@ jobs:
         run: cat /tmp/gotest-complement.log | gotestfmt -hide "successful-downloads,successful-tests,empty-packages"
 
       - name: Run in-repo Complement Tests
+        # Always run as long as we attempted to run the original Complement tests.
+        # This lets us get a status report on the in-repo tests, even if the
+        # standard Complement test suite fails.
+        if: always() && steps.run_complement_tests.outcome != 'skipped'
         id: run_in_repo_complement_tests
         # -p=1: We're using `-p 1` to force the test packages to run serially as GHA boxes
         #     are underpowered and don't like running tons of Synapse instances at once.

changelog.d/20161.misc

@@ -0,0 +1 @@
+Run the in-repo Complement test suite in CI, even when the standard Complement suite fails.