main/mobile-config-firefox: upgrade to 4.0.1

I just found that running mobile-config-firefox 4.0.0 without any firefox profile causes a crash in FF ESR (error message about the script and Firefox starting without the custom config; until user manually restarts it, then it works). This slipped through my earlier testing unfortunately but here's a fixup release.

https://gitlab.com/postmarketOS/mobile-config-firefox/-/tags/4.0.1

Needs to be backported to v22.12.