ci: Make 'rspec:feature-flags' fail for MRs with no Slack notification

Signed-off-by: Rémy Coutable <remy@rymai.me>

.gitlab/ci/rails.gitlab-ci.yml

@@ -502,7 +502,6 @@ rspec:feature-flags:
     - .coverage-base
     - .rails:rules:rspec-feature-flags
   stage: post-test
-  allow_failure: true
   # We cannot use needs since it would mean needing 84 jobs (since most are parallelized)
   # so we use `dependencies` here.
   dependencies:
@@ -522,7 +521,11 @@ rspec:feature-flags:
     - memory-on-boot
   script:
     - run_timed_command "bundle install --jobs=$(nproc) --path=vendor --retry=3 --quiet --without default development test production puma unicorn kerberos metrics omnibus ed25519"
-    - 'run_timed_command "bundle exec scripts/used-feature-flags" || (scripts/slack master-broken "☠️ \`${CI_JOB_NAME}\` failed! ☠️ See ${CI_JOB_URL}" ci_failing "GitLab Bot" && exit 1)'
+    - if [ "$CI_COMMIT_BRANCH" == "$CI_DEFAULT_BRANCH" ]; then
+        run_timed_command "bundle exec scripts/used-feature-flags" || (scripts/slack master-broken "☠️ \`${CI_JOB_NAME}\` failed! ☠️ See ${CI_JOB_URL}" ci_failing "GitLab Bot" && exit 1);
+      else
+        run_timed_command "bundle exec scripts/used-feature-flags";
+      fi
 
 # EE/FOSS: default refs (MRs, master, schedules) jobs #
 #######################################################

.gitlab/ci/rules.gitlab-ci.yml

@@ -879,6 +879,7 @@
     - <<: *if-not-ee
       when: never
     - <<: *if-master-schedule-2-hourly
+      allow_failure: true
     - <<: *if-merge-request-title-run-all-rspec
 
 .rails:rules:master-schedule-nightly--code-backstage: