Correctly handle timeouts in oauth

Author: TheOneRing

changelog/unreleased/10373

@@ -0,0 +1,3 @@
+Bugfix: Correctly detect timeouts during token refrshs
+
+https://github.com/owncloud/client/pull/10373

src/libsync/creds/httpcredentials.cpp

@@ -293,12 +293,15 @@ bool HttpCredentials::refreshAccessTokenInternal(int tokenRefreshRetriesCount)
             timeout = 0s;
             break;
         case QNetworkReply::HostNotFoundError:
-            Q_FALLTHROUGH();
+            [[fallthrough]];
         case QNetworkReply::TimeoutError:
-            Q_FALLTHROUGH();
+            [[fallthrough]];
+        // Qt reports OperationCanceledError if the request timed out
+        case QNetworkReply::OperationCanceledError:
+            [[fallthrough]];
         case QNetworkReply::TemporaryNetworkFailureError:
             nextTry = 0;
-            Q_FALLTHROUGH();
+            [[fallthrough]];
         default:
             timeout = 30s;
         }