PR: Always use utf-8 when handling QByteArray data in ProcessWorker (Utils)

[ccordoba12]

Description of Changes

• It seems the previous approach (using the Windows code page) was necessary to have compatibility with Python 2.
• That was affecting opening project files in our switcher with the help of fzf.

Issue(s) Resolved

Fixes #22546.

Affirmation

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[ccordoba12]

@dalthviz, could you check that our fzf support works in a project directory that has Chinese and/or Arabic characters in its name? Thanks!

[dalthviz]

@dalthviz, could you check that our fzf support works in a project directory that has Chinese and/or Arabic characters in its name? Thanks!

Checked using Spyder 6.0.1 from the Windows installer and also this PR with a project called test_project_项目 and seems to me that things with fzf work in both cases 🤔

[dalthviz]

Thanks @ccordoba12 ! Left a comment related with that maybe it could be worthy to add some sort of context of why now the function should always return utf-8. Also, maybe is worthy to add some sort of test for this? I'm unsure what is needed to reproduce the issue this fixes but probably having a test should ensure the change done here is enough

[ccordoba12]

Checked using Spyder 6.0.1 from the Windows installer and also this PR with a project called test_project_项目 and seems to me that things with fzf work in both cases 🤔

Ok, thanks for checking @dalthviz. Maybe the problem only appears for computers with a proper Windows Chinese version. In any case, the user that reported issue #22546 verified that this correctly fixes it for them.

[dalthviz]

Thanks @ccordoba12 !

[dalthviz]

@meeseeksdev please backport to 6.x