Avoid seed data execution in CI by replacing db:setup with db:test:prepare

Author: viktorianer

railties/lib/rails/generators/rails/app/templates/github/ci.yml.tt

@@ -126,7 +126,7 @@ jobs:
           DATABASE_URL: postgres://postgres:postgres@localhost:5432
           <%- end -%>
           # REDIS_URL: redis://localhost:6379/0
-        run: bin/rails db:setup test test:system
+        run: bin/rails db:test:prepare test test:system
 
       - name: Keep screenshots from failed system tests
         uses: actions/upload-artifact@v4