Fix pytest coverage dependency in setup.py for testing

Author: Christoph Paulik

setup.py

@@ -89,7 +89,6 @@ def run_tests(self):
         params = {"args": self.test_args}
         if self.cov:
             params["args"] += self.cov
-            params["plugins"] = ["cov"]
         if self.junitxml:
             params["args"] += self.junitxml
         errno = pytest.main(**params)