Merge #10027: Set to nullptr after delete

d93b97f Set to nullptr after delete (practicalswift)

Tree-SHA512: 7201cef4541557ffe31f52ce7527c4b08a2ff5aa1eae5268bdfee5b4843881f8fd115257bef6d1b4dfb71166951950a912ce87aef160ca89c2ca2ae264cfab1b

src/httpserver.cpp

@@ -475,6 +475,7 @@ void StopHTTPServer()
         LogPrint("http", "Waiting for HTTP worker threads to exit\n");
         workQueue->WaitExit();
         delete workQueue;
+        workQueue = nullptr;
     }
     if (eventBase) {
         LogPrint("http", "Waiting for HTTP event thread to exit\n");