Add PHP 8.3 and 8.4 to CI test matrix

Updated the continuous integration workflow to include PHP versions 8.3 and 8.4 in the testing matrix.

Author: koriym

.github/workflows/continuous-integration.yml

@@ -21,6 +21,8 @@ jobs:
           - '8.0'
           - '8.1'
           - '8.2'
+          - '8.3'
+          - '8.4'
     steps:
       - name: Checkout
         uses: actions/checkout@v1