Why not tests for *all* flags?

https://github.com/AppImage/AppImageKit/blob/c7d35fb25e69ed712bec19c2d684ac47cb602cc4/travis/test-appimages.sh#L19-L23

Is there a reason why these newly added tests are limited to `--version`, `--appimage-version` and `--appimage-updateinfo`? What am I missing?

I think adding tests for `--appimage-offset`, `--appimage-signature` is also reasonable...
(`--appimage-mount` maybe not so much... but what about `--appimage-portable-{home,config}`?)