Move the nsis-uninstall.patch to tor-browser repository

That patch is applied on tor-browser-build, but it seems to be a required patch when building for Windows... therefore I think it should be a commit here instead of a patch only applied there.

This is it https://gitlab.torproject.org/tpo/applications/tor-browser-build/-/blob/main/projects/firefox/nsis-uninstall.patch?ref_type=heads