v1.1.0 coverage improved

Author: mshaileshr@gmail.com

contentstack/assetquery.py

@@ -41,9 +41,8 @@ def environment(self, environment):
             >>> result = stack.asset_query().environment('production').find()
         ------------------------------
         """
-        if environment is not None and environment is not '' and isinstance(environment, str):
+        if isinstance(environment, str):
             self.http_instance.headers['environment'] = environment
-        # self.__query_params["environment"] = environment
         return self
 
     def version(self, version):