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>