[Bug] [GUI] Deselecting all files in a torrent to manually select a few reselects all of them at seemingly random points

[Scripter17]

Please, fill all relevant items:

• I have read CONTRIBUTING.rst

• I have tried with the latest pre-release version and I still can reproduce the issue.

Tribler version/branch+revision:

7.10.0

Operating system and version:

Windows 10 20H2

Steps to reproduce the behavior:

Add a torrent, click "deselect all" and try manually selecting some of the files

Expected behavior:

Only the files I manually select will be selected

Actual behavior:

At random points every file is reselected for download

Relevant log file output:

N/A

[ichorid]

Reproduced with 7.10 by deselecting all items and then clicking on the "Download anonymously" checkbox. Apparently, the state of file selection checkboxes is reset on some actions within dialog.