Issue: https://gitlab.com/gitlab-org/gitlab/-/issues/336618

Gitaly deprecated and removed Namespace Service, we can remove
a repository instead

The allowed commands must be scoped to namespaces:

- git push/pull/archive
- git lfs authenticate

GitLab Shell detects that the passed key is a certificate and
requests /authorized_certs instead of /authorized_keys endpoint

This explicitly imports gitaly v16 instead of v15 and removes the
old one from `go.mod`.

Prior to this change personal access tokens without a ttl would never
expire. In Gitlab 15.4 we deprecated non-expiring tokens and are
scheduled for removal in 16.0.

https://gitlab.com/gitlab-org/gitlab/-/issues/369122

This change alters the gitlab-shell command for creating tokens to
ensure add a default limit of 30 days.

Closes https://gitlab.com/gitlab-org/gitlab-shell/-/issues/640

It imitates a push to the secondary and verifies that the push
is redirected to the primary

This commit also excludes gitlab-shell from dependencies:

Gitaly specifies Gitlab Shell as a dependency as well in order
to use gitlabnet client to perform API endpoints to Gitlab Rails.
As a result, Gitlab Shell requires Gitaly -> Gitaly requires an
older version of Gitlab Shell -> that version requires an older
version of Gitlab Shell, etc. Let's use exclude to break the
chain earlier

After https://gitlab.com/gitlab-org/gitaly/-/merge_requests/4766
has been introduced, the test started fail because we basically
cancel the git-receive-pack after the output is received

This commit gracefully closes the connection to make the test
pass

While gitlab-shell currently has a major version of v14, the module path
it exposes is not using that major version like it is required by the Go
standard. This makes it impossible for dependents to import gitlab-shell
as a dependency without using a commit as version.

Fix this by changing the module path of gitlab-shell to instead be
`gitlab.com/gitlab-org/gitlab-shell/v14` and adjust all imports
accordingly.

Changelog: fixed

- If an integer is specified, we assume that these are seconds
- A duration of format "500ms", "10s", "1m", etc... accepted