Several duplicate rows merge when clicking "create" several times

[hadley0828]

Describe the bug
For the tables in conference management UI, several duplicate rows merge when the user click the create button several time in a short time.

To Reproduce
Steps to reproduce the behavior:

1. Go to 'manage conference'
2. Go to 'Program People'
3. Click on '+ 'button' at the top of the table
4. Input the 'Name' and 'Affiliation' input fields with some values
5. Click on 'Create' button 3 times(or more) in 1 second
6. Wrong results merge

Expected behavior
Only one new row will be added into the table

Screenshots

Desktop (please complete the following information):

• OS: MacOS 11.4
• Browser: Chrome