Drop locales from torbutton, since we will inject them in tor-browser-build

As a part of the torbutton and locale migration (#41378 (closed), #40924) we moved our translation inside this repository.

This is not very ideal, because we'll keep modifying our patchset only for the strings.

Injecting everything on tor-browser-build is a better solution, because we avoid that, and we can update the strings during the usual build process.

In addition to that, it allows us to do nice things such as tor-browser-build#40679 (closed).