Ignore coverage of common context manager methods

Author: Lukasa

hyper/common/connection.py

@@ -109,10 +109,10 @@ def request(self, method, url, body=None, headers={}):
 
     # The following two methods are the implementation of the context manager
     # protocol.
-    def __enter__(self):
+    def __enter__(self):  # pragma: no cover
         return self
 
-    def __exit__(self, type, value, tb):
+    def __exit__(self, type, value, tb):  # pragma: no cover
         self.close()
         return False  # Never swallow exceptions.