venus/ci: Temporarily disable jobs

There are too many failures. The job can be re-enabled when these have
been fixed (e.g. with skips) and the new lower fraction has been
stress-tested.

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/29709>

src/virtio/ci/gitlab-ci.yml

@@ -1,7 +1,7 @@
 include:
   - local: 'src/virtio/ci/gitlab-ci-inc.yml'
 
-venus-lavapipe:
+.venus-lavapipe:
   extends:
     - .deqp-test
     - .venus-lavapipe-test