Clear server/key when enabling/disabling protected mode

[mhoyer-streamlabs]

When a user switches to Recommended Settings, they key is cleared but the server also needs to be cleared (service is automatically cleared when the stream type changes); uncleared previous settings can cause incorrect information to be displayed/used.

One scenario:

1. Stream to Kick using recommended settings
2. End stream and exit the app
3. Restart the app, open Stream settings, go to Custom Ingest
4. Service = Twitch but server/stream key = Kick
5. Save these settings and go live works correctly even though service = Twitch (also stored as Twitch in service.json)

The same issue exists for both enabling and disabling protected mode (Recommended Settings vs Custom Ingest), so clear the fields in both cases.

Incorrect settings displayed: