ci: add basepath parameter to phpcs command

.gitlab-ci.yml

@@ -7,7 +7,7 @@ codestyle_check:
   stage: test
   script:
   - composer global require squizlabs/php_codesniffer=^3 micheh/phpcs-gitlab=^1
-  - /tmp/vendor/bin/phpcs -v -s -n -p --standard=PSR1,PSR2,PSR12 --no-cache --colors --report=full --report-/tmp/vendor/micheh/phpcs-gitlab/src/Report/Gitlab.php=phpcs-quality-report.json $CI_PROJECT_DIR
+  - /tmp/vendor/bin/phpcs -v -s -n -p --standard=PSR1,PSR2,PSR12 --no-cache --colors --report=full --report-/tmp/vendor/micheh/phpcs-gitlab/src/Report/Gitlab.php=phpcs-quality-report.json --basepath=$CI_PROJECT_DIR $CI_PROJECT_DIR
   artifacts:
     reports:
       codequality: phpcs-quality-report.json