update php versions to test against

Author: tomschlick

.github/workflows/run-tests.yml

@@ -13,7 +13,7 @@ jobs:
       fail-fast: true
       matrix:
         os: [ubuntu-latest]
-        php: [8.0, 8.1]
+        php: [8.0, 8.1, 8.2, 8.3, 8.4]
         stability: [prefer-stable]
 
     name: PHP ${{ matrix.php }}