Context:
Our user multi-select are asynchronous, which currently not fully supported with the carbon multi-select.
We need to implement workarounds for all the issues that would come up by using the carbon multi-select.

AT:

• Implement a user multi-select based on carbon
• Replace the existing user multi-selects with the new one

Testing notes:
Test the new carbon user multi-select which can be found in the following places:

• Assignee filter (We should test both the report and the dashboard assignee filter)
• Add user to collection
• Edit event based process permissions
• Configure process owner in processes dashboards page