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.

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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!