use PHP 8.4 in codestyle check

Author: mspirkov

.github/workflows/build.yml

@@ -58,7 +58,7 @@ jobs:
             - name: Install PHP
               uses: shivammathur/setup-php@v2
               with:
-                  php-version: '7.4'
+                  php-version: '8.4'
                   tools: cs2pr
 
             - name: Get composer cache directory