.gitlab-ci: tests-spawn, enable non-integration

Enable all the tests that aren't marked as being integration, as we
ratchet up the required support for spawn mode.

Note that this also doesn't include tests that aren't under the `tests/`
directory.
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index f669e19..f77c485 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -199,7 +199,8 @@
     - mkdir -p "${INTEGRATION_CACHE}"
     - useradd -Um buildstream
     - chown -R buildstream:buildstream .
-    - su buildstream -c "tox -- ${PYTEST_ARGS} tests/{artifactcache,cachekey,elements,format,frontend,internals,plugins,sourcecache}"
+    # Note that we're not specifying '--integration' here yet.
+    - su buildstream -c "tox -- --color=yes -n 2 tests/"
 
 # Run type checkers
 mypy: