ensure the GCS library and dependencies get included in the scan

.github/workflows/snyk-scan.yml

@@ -14,6 +14,8 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@master
+      - name: Install Google Cloud Storage
+        run: composer require google/cloud-storage
       - name: Run Snyk to check for vulnerabilities
         uses: snyk/actions/php@master
         continue-on-error: true # To make sure that SARIF upload gets called