Update name of file in CPP repo. (firebase#3901)

To match the change done in the IOS repo

firebase/firebase-ios-sdk#10009

Author: rlazo

.github/workflows/update-cpp-sdk-on-release.yml

@@ -71,5 +71,5 @@ jobs:
 
       - name: Trigger firebase-cpp-sdk update
         run: |
-          pip install -r scripts/gha/requirements.txt
+          pip install -r scripts/gha/python_requirements.txt
           python scripts/gha/trigger_workflow.py -t ${{ steps.generate-token.outputs.token }} -w update-dependencies.yml -p updateAndroid 1 -p updateiOS 0 -p comment "[Triggered]($GITHUB_SERVER_URL/$GITHUB_REPOSITORY/actions/runs/$GITHUB_RUN_ID) by [firebase-android-sdk $(date '+%b %d') release]($GITHUB_SERVER_URL/$GITHUB_REPOSITORY/commit/${{ github.sha }})." -s 10 -A