[Infra] Require firestore status check only if firestore code changes

Author: ncooke3

.github/workflows/firestore.yml

@@ -551,7 +551,7 @@ jobs:
   # to be used as a required check for merging.
   check-required-tests:
     runs-on: ubuntu-latest
-    if: always()
+    if: needs.changes.outputs.changed == 'true'
     name: Check all required Firestore tests results
     needs: [cmake, cmake-prod-db, xcodebuild, spm-source, spm-binary]
     steps: