One-click temporary license

Description

I think we should use EE for the i2p demo, so it should be super easy to have a license. One-click and no additional setup would be perfect.

Proposals

Demo mode when using EE without license: enabled by default (?)

Doesn't allow more than 1 user (more needed for any features?) and expires after a single day.

Alternatively, uploading a license before installation would be nice, but hard to do with quick setup things like K8s.

Links / references

• Demo: https://about.gitlab.com/handbook/sales/demo/
• EE version of the Idea to Production demo: https://gitlab.com/gitlab-org/gitlab-ce/issues/28591