Fix clover.xml path

Author: vukanac

.travis.yml

@@ -30,4 +30,4 @@ script:
 # public repo on Travis CI (without token)
 after_success:
   - bash <(curl -s https://codecov.io/bash)
-  - travis_retry php vendor/bin/php-coveralls
+  - travis_retry php vendor/bin/php-coveralls -x coverage.xml