Appimage has low quallity Icon in KDE

[Ma5t3rful]

Distribution Arch:

Issue/Bug Description:
It seems that the the Icon that lives in the root of the Appimage is pretty low res which leads to show a pretty low res icon in KDE.

I could fix the issue by these steps:

1. I extracted the appimage using --appimage-extract
2. removed the symlink and created another from usr/share/icons/hicolor/512x512/apps/org.System76.Popsicle.png using ln command
3. packed it up again using appimagetool
   Before:
   
   After:
   

Expected behavior:
a high res icon for the Appimage.

Other Notes: