dispatch: use auto-reset event for dispatch queue
Use an auto-reset event for the dispatch queue on Windows.  On Linux,
`eventfd` is used, which is auto-reset unless `EFD_SEMAPHORE` is
specified.  This mirrors that behaviour.  The test suite continues to
pass after this change.
@@ -6560,7 +6560,7 @@ _dispatch_runloop_queue_handle_init(void *ctxt)
handle = fd;
#elif defined(_WIN32)
HANDLE hEvent;
- hEvent = CreateEventW(NULL, /*bManualReset=*/TRUE,
+ hEvent = CreateEventW(NULL, /*bManualReset=*/FALSE,
/*bInitialState=*/FALSE, NULL);
if (hEvent == NULL) {
DISPATCH_INTERNAL_CRASH(GetLastError(), "CreateEventW");
