[bugfix] only get HTTPStatus enum in site_detect check_response

- The description is used later within the exception message.
  Instead of raising AttributeError a ClientError is raised then.
- Update tests accordingly.

Bug: T334728
Change-Id: If0eb80e5cf08115550ce6563b3759152256d2867
---
M tests/site_detect_tests.py
M pywikibot/site_detect.py
2 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/pywikibot/site_detect.py b/pywikibot/site_detect.py
index 5dde965..c79983f 100644
--- a/pywikibot/site_detect.py
+++ b/pywikibot/site_detect.py
@@ -295,7 +295,7 @@
     ]:  # highest http status code first
         if response.status_code >= status_code:
             try:
-                status = HTTPStatus(response.status_code).description
+                status = HTTPStatus(response.status_code)
             except ValueError as err:
                 m = re.search(r'\d{3}', err.args[0], flags=re.ASCII)
                 if not m:
diff --git a/tests/site_detect_tests.py b/tests/site_detect_tests.py
index 024f829..ca3be3c 100755
--- a/tests/site_detect_tests.py
+++ b/tests/site_detect_tests.py
@@ -14,7 +14,7 @@
 import requests.exceptions as requests_exceptions
 
 import pywikibot
-from pywikibot.exceptions import ServerError
+from pywikibot.exceptions import ClientError, ServerError
 from pywikibot.site_detect import MWSite
 
 from tests.aspects import PatchingTestCase, TestCase
@@ -38,14 +38,14 @@
             self.assertIsInstance(MWSite(url), MWSite)
 
     def assertNoSite(self, url: str):
-        """
-        Assert a url is not a MediaWiki site.
+        """Assert a url is not a MediaWiki site.
 
         :param url: Url of tested site
         :raises AssertionError: Site under url is MediaWiki powered
         """
         with self.assertRaises((AttributeError,
-                                ConnectionError,
+                                ClientError,
+                                ConnectionError,  # different from requests
                                 RuntimeError,
                                 ServerError,
                                 requests_exceptions.ConnectionError,

