Don't show outdated tracker message

PR #19616.
Closes #19612.

src/base/bittorrent/torrentimpl.cpp

@@ -180,6 +180,10 @@ namespace
                 {
                     trackerEndpoint.message = QString::fromLocal8Bit(infoHash.last_error.message());
                 }
+                else
+                {
+                    trackerEndpoint.message.clear();
+                }
             }
         }
 #else
@@ -239,6 +243,10 @@ namespace
             {
                 trackerEndpoint.message = QString::fromLocal8Bit(endpoint.last_error.message());
             }
+            else
+            {
+                trackerEndpoint.message.clear();
+            }
         }
 #endif