Add Gradle Enterprise creds to PR builds

Closes gh-14249

Author: sjohnr

.github/workflows/pr-build-workflow.yml

@@ -2,6 +2,11 @@ name: PR Build
 
 on: pull_request
 
+env:
+  GRADLE_ENTERPRISE_CACHE_USERNAME: ${{ secrets.GRADLE_ENTERPRISE_CACHE_USER }}
+  GRADLE_ENTERPRISE_CACHE_PASSWORD: ${{ secrets.GRADLE_ENTERPRISE_CACHE_PASSWORD }}
+  GRADLE_ENTERPRISE_ACCESS_KEY: ${{ secrets.GRADLE_ENTERPRISE_SECRET_ACCESS_KEY }}
+
 permissions:
   contents: read