Generate packs before test bundle build

Author: justin808

.github/workflows/ci.yml

@@ -62,6 +62,11 @@ jobs:
       - name: Install JavaScript dependencies
         run: npm ci
 
+      - name: Generate React on Rails packs
+        env:
+          RAILS_ENV: test
+        run: bundle exec rake react_on_rails:generate_packs
+
       - name: Build test bundles
         env:
           RAILS_ENV: test