Add initial support for RPM packaging (#121)

- Add gen-rpm
- Package rpm in CI testing and releases
- Remove fedora 33 from testing (end of life)
- Update arguments for `build_private.sh` and `build_sunshine.sh`

Co-authored-by: ReenigneArcher <42013603+ReenigneArcher@users.noreply.github.com>

CMakeLists.txt

@@ -313,6 +313,7 @@ else()
 		set(SUNSHINE_EXECUTABLE_PATH "sunshine")
 	endif()
 	configure_file(gen-deb.in gen-deb @ONLY)
+	configure_file(gen-rpm.in gen-rpm @ONLY)
 	configure_file(sunshine.desktop.in sunshine.desktop @ONLY)
 	configure_file(sunshine.service.in sunshine.service @ONLY)
 endif()