Minwaita-inkscape-dark is redundant
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#### Summary:
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Gtk can hold two versions of theme in one theme (that's why we have a dark mode switch).
We ship Inkscape with Minwaita-Inkscape which holds a light and dark themes.
Minwaita-inkscape-dark is redundant there is not good reason why we should ship Inkscape with this theme.
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#### Version Info:
```
Inkscape 1.1-alpha (f11df71, 2021-03-31)
GLib version: 2.68.0
GTK version: 3.24.27
glibmm version: 2.66.0
gtkmm version: 3.24.3
libxml2 version: 2.9.10
libxslt version: 1.1.34
Cairo version: 1.17.4
Pango version: 1.48.4
HarfBuzz version: 2.8.0
Poppler version: 20.12.1
OS version: Windows 10 2009
```
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issue