chore: update test matrix to test against 7.2+

Author: joshmanders

.github/workflows/tests.yaml

@@ -13,7 +13,7 @@ jobs:
     strategy:
       fail-fast: true
       matrix:
-        php: [8.3]
+        php: [7.2, 7.3, 7.4, 8.0, 8.1, 8.2, 8.3, 8.4]
 
     name: PHP ${{ matrix.php }}