Add PHP 8.1 in GitHub action

Author: peter279k

.github/workflows/continuous-integration.yml

@@ -66,12 +66,14 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        php-version: ["7.3", "7.4", "8.0"]
+        php-version: ["7.3", "7.4", "8.0", "8.1"]
         operating-system: ["ubuntu-latest"]
         experimental: [false]
         include:
           - php: "8.0"
             composer-options: "--ignore-platform-req=php"
+          - php: "8.1"
+            composer-options: "--ignore-platform-req=php"
 
     steps:
       - name: Checkout
@@ -87,4 +89,4 @@ jobs:
         run: composer install --no-progress --prefer-dist --optimize-autoloader ${{ matrix.composer-options }}
 
       - name: Execute tests
-        run: vendor/bin/phpunit --colors=always --coverage-text
+        run: vendor/bin/phpunit --colors=always --coverage-text

composer.json

@@ -39,5 +39,10 @@
         "analyse": "vendor/bin/phpstan analyse --no-progress",
         "test": "vendor/bin/phpunit",
         "cs": "vendor/bin/phpcs"
+    },
+    "config": {
+        "allow-plugins": {
+            "dealerdirect/phpcodesniffer-composer-installer": true
+        }
     }
 }