[ENG-4961] Allow Gitlab full configuration via V2 API

[Johnetordoff]

Purpose

Allow API users the ability to configure their Gitlab addon node directly via the API.

Changes

• add get and set methods for Gitlab models

QA Notes

Please make verification statements inspired by your code and what your code touches.

• Verify
• Verify

What are the areas of risk?

Any concerns/considerations/questions that development raised?

Documentation

Side Effects

Ticket

https://openscience.atlassian.net/browse/ENG-4961