libtaskmanager: Allow to launch executables

I stumbled upon this when pinning qdbus viewer
and it seems to be the same issue that many people have.

BUG: 433148
FIXED-IN: 5.21.1

libtaskmanager/tasktools.cpp

@@ -839,6 +839,7 @@ void runApp(const AppData &appData, const QList<QUrl> &urls)
             auto *job = new KIO::OpenUrlJob(appData.url);
             job->setUiDelegate(new KNotificationJobUiDelegate(KJobUiDelegate::AutoErrorHandlingEnabled));
             job->setStartupId(KStartupInfo::createNewStartupIdForTimestamp(timeStamp));
+            job->setRunExecutables(true);
             job->start();
 
             if (!appData.id.isEmpty()) {