Fix unreachable service check assertions in cloud_foundry_api oauth error tests (DataDog#24282)

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

Author: mwdd146980

cloud_foundry_api/tests/test_cloud_foundry_api.py

@@ -283,9 +283,10 @@ def test_get_oauth_token_errors(_, __, ___, aggregator, instance):
     check = CloudFoundryApiCheck('cloud_foundry_api', {}, [instance])
     check._http = None  # initialize the _http attribute for mocking
 
-    with mock.patch.object(check, "_http") as http_mock, pytest.raises(RequestException):
+    with mock.patch.object(check, "_http") as http_mock:
         http_mock.get.side_effect = RequestException()
-        check.get_oauth_token()
+        with pytest.raises(RequestException):
+            check.get_oauth_token()
         aggregator.assert_service_check(
             name="cloud_foundry_api.uaa.can_authenticate",
             status=CloudFoundryApiCheck.CRITICAL,
@@ -294,9 +295,10 @@ def test_get_oauth_token_errors(_, __, ___, aggregator, instance):
         )
         aggregator.reset()
 
-    with mock.patch.object(check, "_http") as http_mock, pytest.raises(HTTPError):
+    with mock.patch.object(check, "_http") as http_mock:
         http_mock.get.return_value = mock.MagicMock(raise_for_status=mock.MagicMock(side_effect=HTTPError()))
-        check.get_oauth_token()
+        with pytest.raises(HTTPError):
+            check.get_oauth_token()
         aggregator.assert_service_check(
             name="cloud_foundry_api.uaa.can_authenticate",
             status=CloudFoundryApiCheck.CRITICAL,
@@ -305,9 +307,10 @@ def test_get_oauth_token_errors(_, __, ___, aggregator, instance):
         )
         aggregator.reset()
 
-    with mock.patch.object(check, "_http") as http_mock, pytest.raises(ValueError):
+    with mock.patch.object(check, "_http") as http_mock:
         http_mock.get.return_value = mock.MagicMock(json=mock.MagicMock(side_effect=ValueError()))
-        check.get_oauth_token()
+        with pytest.raises(ValueError):
+            check.get_oauth_token()
         aggregator.assert_service_check(
             name="cloud_foundry_api.uaa.can_authenticate",
             status=CloudFoundryApiCheck.CRITICAL,