add php 8.4 to matrix

Author: joshmanders

.github/workflows/tests.yaml

@@ -13,7 +13,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        php: [8.2, 8.3]
+        php: [8.2, 8.3, 8.4]
         laravel: [11.*]
         include:
           - laravel: 11.*