wasm: fix error report when network request is cancelled

Fixes: QTBUG-73346
Change-Id: I8aaf8fe45f3014e2c9187c554ed86a4d29c03c0b
Reviewed-by: Morten Johan Sørvig <morten.sorvig@qt.io>

src/network/access/qnetworkreplywasmimpl.cpp

@@ -235,6 +235,7 @@ void QNetworkReplyWasmImpl::close()
 void QNetworkReplyWasmImpl::abort()
 {
     Q_D(const QNetworkReplyWasmImpl);
+    setError( QNetworkReply::OperationCanceledError, "Operation canceled" );
     d->doAbort();
 
     close();