Allow PHP 8.1 (#7)

Author: BrunoSpy

composer.json

@@ -14,7 +14,7 @@
         "dino/dompdf-module": "0.*"
     },
     "require": {
-        "php": "~7.4.1 || ~8.0.0",
+        "php": "~7.4.1 || ~8.0.0 || ~8.1.0",
         "laminas/laminas-servicemanager": "^3.4.1",
         "laminas/laminas-modulemanager": "^2.10.1",
         "laminas/laminas-eventmanager": "^3.3.0",