Disable swipe to refresh for Offline Accounts

[quwepiro]

I am using Quillnote without any sync. However I can still swipe down on the main screen and trigger a "refresh".
Personally often when I long press a note I acidentally swipe a bit down and trigger this refresh, which is annoying.

I dont think that this is intended as it has no real use case for an Offline Account.

If no one has the time I could also prepare a pull request as I think it should be not very complicated to fix.
Thank you all for this cool open-source project :)