Add mongodb service

Author: glensc

.github/workflows/tests-mongodb.yml

@@ -14,6 +14,12 @@ jobs:
     env:
       PHPUNIT_VERSION: "7.5"
 
+    services:
+      mongodb:
+        image: percona/percona-server-mongodb:3.6
+        ports:
+          - 27017:27017
+
     steps:
       - name: Checkout Code
         uses: actions/checkout@v2