Add PHP 8.1 to GitHub Actions

Author: Frederick888

.github/workflows/php.yml

@@ -22,7 +22,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-latest]
-        php-version: ["8.0", "7.4", "7.3"]
+        php-version: ["8.1", "8.0", "7.4", "7.3"]
 
     steps:
       - uses: actions/checkout@v2
@@ -32,7 +32,7 @@ jobs:
           echo "::set-output name=hash::$(git rev-parse HEAD)"
 
       - name: Cancel Previous Runs
-        if: contains(matrix.os, 'ubuntu') && contains(matrix.php-version, '8.0')
+        if: contains(matrix.os, 'ubuntu') && contains(matrix.php-version, '8.1')
         uses: styfle/cancel-workflow-action@0.6.0
         with:
           access_token: ${{ github.token }}