Run gRPC workflow on PHP 8.3

Author: jeromegamez

.github/workflows/grpc-tests.yml

@@ -29,13 +29,13 @@ concurrency:
 
 jobs:
   grpc-tests:
-    name: gRPC Tests (PHP 8.4)
+    name: gRPC Tests (PHP 8.3)
     runs-on: ubuntu-latest
     continue-on-error: true
     if: ${{ github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name == github.repository }}
 
     env:
-      php-version: '8.4'
+      php-version: '8.3'
       extensions: grpc
       key: cache-v1