Remove temporary GHA trigger (#12434)

Author: paulb777

.github/workflows/zip.yml

@@ -7,8 +7,6 @@ on:
     - '.github/workflows/zip.yml'
     - 'scripts/build_non_firebase_sdks.sh'
     - 'Gemfile*'
-    # DELETE BEFORE pushing
-    - 'FirebaseCore.podspec'
     # Don't run based on any markdown only changes.
     - '!ReleaseTooling/*.md'
   schedule: