Revert "GH Actions: apply work-around for testing against PHP 8.5"

This reverts commit 1fe0982 / PR 177 as it is no longer needed.

Ref: https://github.com/composer/composer/releases/tag/2.8.11

Author: jrfnl

.github/workflows/tests.yml

@@ -28,7 +28,7 @@ jobs:
     - name: Setup PHP
       uses: shivammathur/setup-php@v2
       with:
-        php-version: ${{ matrix.php-versions == '8.5' && '8.4' || matrix.php-versions }}
+        php-version: ${{ matrix.php-versions }}
         extensions: mbstring
         ini-values: zend.assertions=1, error_reporting=-1, display_errors=On, display_startup_errors=On, log_errors_max_len=0
         coverage: none
@@ -49,14 +49,5 @@ jobs:
         composer-options: --ignore-platform-reqs
         custom-cache-suffix: $(date -u "+%Y-%m")
 
-    - name: "Setup PHP again (PHP 8.5)"
-      if: ${{ matrix.php-versions == '8.5' }}
-      uses: shivammathur/setup-php@v2
-      with:
-        php-version: ${{ matrix.php-versions }}
-        extensions: mbstring
-        ini-values: zend.assertions=1, error_reporting=-1, display_errors=On, display_startup_errors=On, log_errors_max_len=0
-        coverage: none
-
     - name: Run tests
       run: vendor/bin/phpunit tests