docs: Fix link for issue from FAQ

[c3d]

This fixes the link to issue #20 in magit/forge (and not magit/ghub).

Fixs: #428

Signed-off-by: Christophe de Dinechin [email protected]

[tarsius]

Thanks!

I regenerated because the version strings were not updated and learned two things.

1. My tools don't update the version strings to the expected form like 0.3.0 (v0.3.0-1-gfb22dda9+1) for the very first commit after a release. (Oh well.)
2. My texinfo inserts some trailing whitespace, where yours doesn't. (I decide to keep it because otherwise it would get readded the next time I make a change.)