Merge pull request swiftlang#10415 from z2oh/cherrypick-20240723-clear-win-thread-name-container

[🍒] [lldb] Clear thread name container before writing UTF8 bytes (llvm#134150)

Author: JDevlieghere

lldb/source/Plugins/Process/Windows/Common/TargetThreadWindows.cpp

@@ -191,6 +191,7 @@ const char *TargetThreadWindows::GetName() {
   if (SUCCEEDED(GetThreadDescription(
           m_host_thread.GetNativeThread().GetSystemHandle(), &pszThreadName))) {
     LLDB_LOGF(log, "GetThreadDescription: %ls", pszThreadName);
+    m_name.clear();
     llvm::convertUTF16ToUTF8String(
         llvm::ArrayRef(reinterpret_cast<char *>(pszThreadName),
                        wcslen(pszThreadName) * sizeof(wchar_t)),