QGIS crashes during the loading of SLD

[Gpetrak]

QGIS crashes when the user tries to load a layer the WFS. The crash happens in the following line:

https://github.com/GeoNode/QGISGeoNodePlugin/blob/main/src/qgis_geonode/styles.py#L49

Probably the error is related with encoding issues since this that happens only in layers with non-english characters.

[Gpetrak]

After more investigation, I realized that the error is not related with encoding issues. The QGIS crashes when the retrieved SLD from GeoServer includes comments especially before the element NamedLayer. Thus to fix the error I had to create a remove_comments_from_sld function, which scans the SLD and removes the comments.
The corresponding PR is available here #298