Add PHP 8.3 and 8.4 to the test matrix

Author: e1himself

.github/workflows/test.yml

@@ -6,7 +6,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        php: [ '7.1', '7.2', '7.3', '7.4', '8.0', '8.1', '8.2' ]
+        php: [ '7.1', '7.2', '7.3', '7.4', '8.0', '8.1', '8.2', '8.3', '8.4' ]
 
     steps:
       - uses: actions/checkout@master