GH Actions: run tests against PHP 8.2

The first alpha of PHP 8.2 was released nearly two weeks ago, so let's start testing against PHP 8.2

Notes:
* Test runs again PHP 8.1 were still marked as "allowed to fail".
    This has been changed to allow PHP 8.2 to fail, but no longer allow failures for PHP 8.1.

.github/workflows/ci.yml

@@ -37,9 +37,9 @@ jobs:
     strategy:
       matrix:
         operating-system: ['ubuntu-latest']
-        php-versions: ['7.1', '7.2', '7.3', '7.4', '8.0', '8.1']
+        php-versions: ['7.1', '7.2', '7.3', '7.4', '8.0', '8.1', '8.2']
 
-    continue-on-error: ${{ matrix.php-versions == '8.1' }}
+    continue-on-error: ${{ matrix.php-versions == '8.2' }}
 
     steps:
       - name: Checkout
@@ -56,12 +56,12 @@ jobs:
       - name: Modernize dependencies
         run: composer require --dev --no-update "phpunit/phpunit:>=4"
 
-      - name: Install Composer dependencies (PHP < 8.1)
-        if: ${{ matrix.php-versions != '8.1' }}
+      - name: Install Composer dependencies (PHP < 8.2)
+        if: ${{ matrix.php-versions != '8.2' }}
         uses: "ramsey/composer-install@v2"
 
-      - name: Install Composer dependencies - ignore-platform-reqs (PHP 8.1)
-        if: ${{ matrix.php-versions == '8.1' }}
+      - name: Install Composer dependencies - ignore-platform-reqs (PHP 8.2)
+        if: ${{ matrix.php-versions == '8.2' }}
         uses: "ramsey/composer-install@v2"
         with:
           composer-options: --ignore-platform-reqs