Update test matrix (#548)

- MongoDB 4.0 hit EOL in April 2022. So removing it from test matrix
- Added Percona Server for MongoDB 5.0
- Updated tip version of MongoDB from 4.2 to 4.4

Author: Shashank Sinha

.github/workflows/go.yml

@@ -22,21 +22,20 @@ jobs:
         go-version:
           - 1.17.x
         image:
-          - mongo:4.0
           - mongo:4.2
           - mongo:4.4
           - mongo:5.0
-          - percona/percona-server-mongodb:4.0
           - percona/percona-server-mongodb:4.2
           - percona/percona-server-mongodb:4.4
+          - percona/percona-server-mongodb:5.0
         os: [ubuntu-latest]
         may-fail: [false]
 
         include:
           # test only one image on tip to detect major Go changes earlier
           # without wasting too much time on CI
           - go-version: tip
-            image: mongo:4.2
+            image: mongo:4.4
             os: ubuntu-latest
             may-fail: true