Cursor placed at incorrect position when clicking at the end of bullet with a sub-bullet

Where there are bullets with sub-bullets, clicking the mouse to the right of the main bullet places the cursor at the beginning of the text of the bullet as opposed to the end of the text of the bullet.

##### Steps to Reproduce

1. Go to https://trix-editor.org/ and clear the content
2. Create a bulleted list (say A, B, C)
3. Add sub-bullets to B, call it B1 and B2
4. Click mouse far to the right of B1
5. Cursor is placed at the end of B1 as expected
6. Click mouse far to the right of B
7. Cursor is placed at the beginning of B. This is not expected, the cursor should be placed at the end of B instead

##### Details

* Trix version: 1.3.1
* Browser name and version: Chrome Version 90.0.4430.212 (Official Build) (x86_64)
* Operating system: MacOS 11.3.1