discover: switch appstream to tag, add libsoup, python-pyparsing and libxmlb,...
- Appstream switched to tag because master uses Qt6
- Two dependencies libsoup and python-pyparsing were required to build
- libfuse moved the build system to meson and I took the liberty of updating it at the same time
Depends on plasma/discover!552 (merged)
Edited by Nate Graham