Gitaly TCP no longer working in gitaly/client go library

Regression introduced by !972 (merged). Fixed by !974 (merged).

This regression prevented Go Gitaly clients that use the gitlab.com/gitlab-org/gitaly/client library from connecting to Gitaly servers over TCP. This regression got released in Gitaly 0.133.0. The fix got released in 1.0.0.

We are adding test coverage for this regression in !968 (merged).