Fix user env variables for GitLab repos in subgroups

[corneliusludmann]

This allows projects like 'foo/bar/baz' where 'foo/bar' is the owner and 'baz' the user.

Assuming this repo: https://gitlab.com/gp-test-group/gp-test-subgroup/gp-test-project-in-subgroup

owner: gp-test-group/gp-test-subgroup
repo:  gp-test-project-in-subgroup

These repo patterns work:

*/*
gp-test-group/gp-test-subgroup/gp-test-project-in-subgroup
gp-test-group/gp-test-subgroup/*
*/gp-test-project-in-subgroup

These do not work (for the given project):

gp-test-group/*
gp-test-group/*/gp-test-project-in-subgroup
*/gp-test-subgroup/gp-test-project-in-subgroup

How to test

• Set environment variables on http://corneliusludmann-environment-variables-1358.staging.gitpod-dev.com/settings/, e.g. for the repo patterns listed above
• Open the repo and make sure that the env vars are there.
• Run gp env FOO=bar and check that the env var is listed on the settings page.

Corresponding issue

Issue: #1358

[svenefftinge]

LGTM, thanks! (Also works well)