Changed PHP to 8.0 for coverage tests

Author: Andrey Helldar

.github/workflows/coverage.yml

@@ -18,7 +18,7 @@ jobs:
             -   name: Setup PHP
                 uses: shivammathur/setup-php@v2
                 with:
-                    php-version: 7.4
+                    php-version: 8.0
                     extensions: curl, mbstring, zip, pcntl, pdo, pdo_sqlite, iconv
                     coverage: xdebug