Hide warning about missing private key when it was fixed using Preferences

1. have a cloud 2. create a key, save private part. 3. Go to preferences and remove that private key from keys being used 4. Launch instance 5. Select key you have created before 6. You can see a little warning saying "SSh key not found ..." 7. Fix it, click 'Show private keys in preferences' link and re-add your .pem key Currently: warning is still displayed Expected: warning disappears, since your private key is available