* Fix filename for libweaver.so
CMake was adding an extra "lib" prefix on linux, with filename resulting
in "liblibweaver.so". Now it generates it as "libweaver.so."
* Add Linux workflow
The workflow runs on ubuntu and creates 2 arficacts: libweaver.so and an
AppImage containing the SI Editor GUI app.
Also adding a .desktop file as required for building an AppImage.
* ci: try to fix deprecated workflow
* ci: update ffmpeg version
surely this won't break anything Clueless
* ci: let's try this
* ci: try this
* ci: try different ffmpeg cmake arg
* ci: temporarily disable releases upload
qt 6 version is a bit unstable right now so we wanna keep the qt 5 version available