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

parse logic will only run if the executable accept args.
healthcheck is the only one not accepting arguments.

This reverts commit 869aeb9057962b089abfd8ce0b6d4a0962bbb154