[GRASS-git] [OSGeo/grass] 80203e: Show ModelRelation in white on dark mode (#2997)

[Martin Landa]

  Branch: refs/heads/releasebranch_8_3
  Home:   https://github.com/OSGeo/grass
  Commit: 80203efac1207beb9e952f647ff1b51c48165fb1
      https://github.com/OSGeo/grass/commit/80203efac1207beb9e952f647ff1b51c48165fb1
  Author: Martin Landa <landa.martin at gmail.com>
  Date:   2023-06-04 (Sun, 04 Jun 2023)

  Changed paths:
    M gui/wxpython/gmodeler/model.py

  Log Message:
  -----------
  Show ModelRelation in white on dark mode (#2997)

* use black brush when exporting model to image