Don't check for updates in the guest session

[danirabbit]

What Happened?

AppCenter runs in the background and checks for updates when run in the guest session

Steps to Reproduce

1. Have some updates available
2. Start a guest session
3. AppCenter sends an updates notification

Expected Behavior

Guests shouldn't be managing updates. We definitely shouldn't show an updates notification to guests, and tbh we probably should not even show them anything to do with updates in AppCenter at all

OS Version

7.x (Horus)

Software Version

Latest release (I have run all updates)

Log Output

No response

Hardware Info

No response