chore: test against PHP 8.5 (#58)

* chore(ci): bump actions/checkout version
* chore(ci): test against php 8.5

Author: W0rma

.github/workflows/main.yml

@@ -11,11 +11,11 @@ jobs:
 
     strategy:
       matrix:
-        php: [8.1, 8.2, 8.3, 8.4]
+        php: [8.1, 8.2, 8.3, 8.4, 8.5]
 
     steps:
     - name: Checkout code
-      uses: actions/checkout@v4
+      uses: actions/checkout@v6
 
     - name: Setup PHP
       uses: shivammathur/setup-php@v2