[JIRAALIGN-1350] Drop Down User List Takes A Very Long Time To Load As Companies Scale (Active User Count 10K +)[JIRAALIGN-1350]

Issue Summary

We need to look into redesigning how our user drop-down field for public checklist load all users in the system. When we exceed more than 10K users we are seeing delays and latency. As an organization scale, this could become a bigger issue we need to have batman review this and provide a solution.  Would it be possible to convert this user list to implement pagination similar to what we do on programs and teams when adding/searching for users.

Steps to Reproduce

1. Make sure there are 10k or more users active in the system 
2. Then Click the checklist
3. Then select a public checklist
4. Then Click the user drop-down list 

Expected Results

We should duplicate how our program manage users & team manage users functionality works

Actual Results

Performance impact when loading public list

Workaround

No workaround at this time