Hints for saga in main

Warnings

• asv-icon-format-unsupported
  org.saga_gis.saga_gui.appdata.xml:8 - https://sourceforge.net/p/saga-gis/code/ci/master/tree/saga-gis/src/saga_core/saga_gui/res/saga_icon_192.png?format=raw
  This icon uses an unsupported file format. Icons should be PNG, JPEG-XL (`.jxl`) or vector graphics (`.svg`/`.svgz`) images.