Rename mention of gitlab-git-http-server to gitlab-workhorse

[ci skip]

Closes https://github.com/gitlabhq/gitlabhq/issues/9904

doc/update/8.1-to-8.2.md

@@ -142,7 +142,7 @@ git diff origin/8-1-stable:lib/support/nginx/gitlab origin/8-2-stable:lib/suppor
 If you are using Apache instead of NGINX please see the updated [Apache templates].
 Also note that because Apache does not support upstreams behind Unix sockets you
-will need to let gitlab-git-http-server listen on a TCP port. You can do this
+will need to let gitlab-workhorse listen on a TCP port. You can do this
 via [/etc/default/gitlab].
 [Apache templates]: https://gitlab.com/gitlab-org/gitlab-recipes/tree/master/web-server/apache