Always add a reason to erroneous HTTP responses

Otherwise, `aiohttp` cannot parse the response with the trailing space in the status — `"HTTP/1.1 555 "` — since `"555 ".split()` returns only one element, and the whole string `"555 "` is used as the status with expectations of being a 3-digit numeric.

Signed-off-by: Sergey Vasilyev <nolar@nolar.info>

tests/k8s/test_events.py

@@ -76,7 +76,7 @@ async def test_no_events_for_events(
 async def test_api_errors_logged_but_suppressed(
         resp_mocker, aresponses, hostname, settings, logger, assert_logs):
 
-    post_mock = resp_mocker(return_value=aresponses.Response(status=555))
+    post_mock = resp_mocker(return_value=aresponses.Response(status=555, reason='oops'))
     aresponses.add(hostname, '/api/v1/namespaces/ns/events', 'post', post_mock)
 
     obj = {'apiVersion': 'group/version',
@@ -161,7 +161,7 @@ async def test_message_is_cut_to_max_length(
 async def test_headers_are_not_leaked(
         resp_mocker, aresponses, hostname, settings, logger, assert_logs, status):
 
-    post_mock = resp_mocker(return_value=aresponses.Response(status=status))
+    post_mock = resp_mocker(return_value=aresponses.Response(status=status, reason='oops'))
     aresponses.add(hostname, '/api/v1/namespaces/ns/events', 'post', post_mock)
 
     obj = {'apiVersion': 'group/version',

tests/k8s/test_watching_infinitely.py

@@ -39,7 +39,7 @@ async def test_exception_escalates(
 
 async def test_infinite_watch_never_exits_normally(
         settings, resource, stream, namespace, aresponses):
-    error = aresponses.Response(status=555)
+    error = aresponses.Response(status=555, reason='oops')
     stream.feed(
         STREAM_WITH_ERROR_410GONE,  # watching restarted
         STREAM_WITH_UNKNOWN_EVENT,  # event ignored