Mobile,Desktop: Fixes #10191: Do not invite user to create new notes in the trash folder

[personalizedrefrigerator]

Summary

This pull request changes the prompt in the trash folder from There are currently no notes. Create one by clicking on the (+) button. to There are no notes in the trash folder. or This subfolder of the trash has no notes..

The new text states "there are no notes in the trash folder" rather than "the trash folder is empty" because it can be shown if only folders are in the trash.

Fixes #10191.

Screenshots

Android

A folder that isn't in the trash:

An empty folder that is in the trash:

An empty trash folder:

Desktop

Testing plan

1. Create an empty folder and open it.
   • Verify that the There are currently no notes. Create one by clicking on the (+) button. message is shown on mobile and No notes in here. Create one by clicking on "New note". is shown on desktop.
2. Move the folder to the trash and open it.
   • Verify that the This subfolder of the trash has no notes. message is shown.
3. Open the trash folder (empty it if there are notes).
   • Verify that the There are no notes in the trash folder. message is shown.

This has been tested successfully on Ubuntu 23.10 and Android 7.