ci: put it back to the previous level

.github/workflows/tests.yml

@@ -4,6 +4,9 @@ on: [push, pull_request]
 
 jobs:
   test:
+    env:
+      DB: ${{ matrix.db }}
+
     runs-on: ubuntu-latest
 
     strategy:
@@ -20,9 +23,6 @@ jobs:
           - '3.1'
 
     services:
-      env:
-        DB: ${{ matrix.db }}
-
       mysql:
         env:
           MYSQL_DATABASE: rating_test