Fix PHP version compatibility issues with PHPStan and PHPMD

.github/workflows/code-quality.yml

@@ -19,7 +19,7 @@ jobs:
       - name: Setup PHP
         uses: shivammathur/setup-php@v2
         with:
-          php-version: '7.4'
+          php-version: '8.0'
           extensions: mbstring, intl, zip
           tools: composer:v2, phpcs
 
@@ -46,7 +46,7 @@ jobs:
       - name: Setup PHP
         uses: shivammathur/setup-php@v2
         with:
-          php-version: '7.4'
+          php-version: '8.0'
           extensions: mbstring, intl, zip
           tools: composer:v2, phpstan
 
@@ -67,7 +67,7 @@ jobs:
       - name: Setup PHP
         uses: shivammathur/setup-php@v2
         with:
-          php-version: '7.4'
+          php-version: '8.0'
           extensions: mbstring, intl, zip
           tools: composer:v2, phpmd