Create VM for Gitlab migration work

Originally created by @zen on #17266 (Redmine)

• This VM will be used to publish our prototypes to some more people within Tails community.
• It can be deleted after the project is done (planned May 2020).
• It is an open question whether Tails will host it’s own Gitlab instance.
• Requirements:
  • root access to setup a Gitlab (after Gitlab is setup, root access might not be needed).
  • 1 core.
  • 4GB RAM.
  • Rounded up the space of all repos + 10G for the base system.
  • doesn’t need to accessible from the outside any proxy mechanism is fine.

Related issues

• Related to tails/sysadmin#15878