GITLAB using depreacted varaibles

[joewashear007]

In the source for the GitLab task, the environment variabke it uses to get the current branch is using an depreacted varaible, See: https://github.com/GitTools/GitVersion/blob/master/src/GitVersionCore/BuildServers/GitLabCi.cs#L40

Here is the depreaction and update notice: https://docs.gitlab.com/ee/ci/variables/deprecated_variables.html#gitlab-90-renamed-variables.

Thank for the good work.!

[zionyx]

Hi @joewashear007, how about an open pull request that addresses this issue for the project, on behalf of all its grateful user base? 😄

[arturcic]

Closed by #1741