Allow users to set the value of a repository variable as another variable

Problem Definition

Users would like to be able to set the value of a repository variable as another variable.
This is possible to do in the Pipelines script, however it is not possible to do so in 'Repository variables' page or 'Workspace variables' pages or in the Deployment variables.

Suggested Solution

Allow users to reference other variables in the above pages as well, as follows: