This puts Vorta on PyQt6 and starts a new main branch 0.9.
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Co-authored-by: real-yfprojects <real-yfprojects@users.noreply.github.com>
Co-authored-by: Manu <3916435+m3nu@users.noreply.github.com>
Co-authored-by: yfprojects <62463991+real-yfprojects@users.noreply.github.com>
This adds trailing lines to files,
removes trailing white space in all the other lines and unifies line endings.
Additionally it formats the test code with `black`.
