Support Self-hosted GitLab

[idanshahar]

Allero currently supports GitLab Cloud. Add support for a Self-Hosted GitLab.
Allow configuring the url a private GitLab for the fetch command.

[jmj0502]

Hey! @idanshahar. I would like to give it a shot. I may need some guidance along the way, tho'.

[dimabru]

hey @jmj0502
Go ahead, I'm assigning you to this issue.

I think the best way to implement it is to add a key to the ConfigurationManager that will include the private gitlab server url.
Then, when creating a client for gitlab, check if private gitlab was configured.

Here's a link to the gitlab client we're using for some references: https://github.com/xanzy/go-gitlab

[jmj0502]

Cool! I'll start to work on the issue as soon as I can 👍

[idanshahar]

Awesome! thanks @jmj0502!