WFS cannot be loaded if layer has previously uploaded styles to geonode

[AdamChyl]

As in the title, if a layer has custom styles loaded from qgis, it is not possible to download this layer again from WFS

buttons disabled after trying to download, layer without styles loads correctly

[AdamChyl]

Fixed, if styling is done using strings from fields and if these strings contain special characters, it will crash.

Add error ignoring in styles.py file: return buffer_.data().decode(encoding=“utf-8”, errors=“ignore”)