diff --git a/.github/workflows/phpunit.yml b/.github/workflows/phpunit.yml
index 897470b..75e9374 100644
--- a/.github/workflows/phpunit.yml
+++ b/.github/workflows/phpunit.yml
@@ -15,4 +15,4 @@ jobs:
       php: >-
         ['8.1', '8.2']
       stability: >-
-        [prefer-lowest, prefer-stable]
+        ['prefer-lowest', 'prefer-stable']