Use dev-commits-doc-all instead of undefined git-doc-all in FDP.

[pauamma_gundo.com]

Summary

This is not enough for pt-br, which also needs a native speaker to define
dev-commits-doc-all in shared/pt-br/mailing-lists.adoc.

File documentation/content/pt-br/books/fdp-primer/overview/_index.po also
contains git-doc-all, but I don't want to change that by hand without a
pt-br translator's go-ahead.

Discussed with: dbaio (in IRC)

Test Plan

lynx . (and drill down to the changed sections)

[dbaio]

Thanks