Drop unsupported PHP versions from CI workflow

Author: andrew-demb

.github/workflows/test.yaml

@@ -12,7 +12,7 @@ jobs:
         strategy:
             matrix:
                 install-args: ['', '--prefer-lowest']
-                php-version: ['7.2', '7.3', '7.4', '8.0']
+                php-version: ['7.4', '8.0']
             fail-fast: false
         steps:
             # Cancel previous runs of the same branch