CI: Name the test job for clearer output

.github/workflows/ci.yml

@@ -4,12 +4,13 @@ on: [push, pull_request]
 
 jobs:
   test:
+    name: "Test on Redis ${{ matrix.redis-version }}, Ruby ${{ matrix.ruby-version }}"
     runs-on: ubuntu-latest
 
     strategy:
       matrix:
         redis-version:
-          - 4.0
+          - '4.0'
           - 4.1
           - 4.2
           - 4.3