UI: Change default autoconfig test bitrate

Changes the default autoconfig test bitrate to 10000kb/s, which will
then be capped by the user's service selection (so it'll still only use
6000 on Twitch for example, but will allow 10000 on Youtube and others).

UI/window-basic-auto-config.cpp

@@ -283,7 +283,7 @@ bool AutoConfigStreamPage::validatePage()
 
 	wiz->customServer = ui->streamType->currentIndex() == 1;
 
-	int bitrate = 6000;
+	int bitrate = 10000;
 	if (!ui->doBandwidthTest->isChecked()) {
 		bitrate = ui->bitrate->value();
 		wiz->idealBitrate = bitrate;