diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 7ddc8f3f2..3c7300467 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -13,7 +13,7 @@ jobs:
       fail-fast: false
       matrix:
         php: [ 7.4, 8.0 ]
-        database: [ mariadb:10.2, mariadb:10.6, mysql:8 ]
+        database: [ 'mariadb:10.2', 'mariadb:10.6', 'mysql:8' ]
     services:
       database:
         image: ${{ matrix.database }}