PanelMenu Icon does not show for entries without sub children

[Rainson12]

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[X ] bug report
[ ] feature request
[ ] support request => Please do not submit support request here, instead see https://forum.primefaces.org/viewforum.php?f=57

Codesandbox Case (Bug Reports)
https://codesandbox.io/s/primereact-test-vsh6z

Current behavior
When setting the icon property for a menu entry the icon is only being rendered if the menu has subitems. That doesnt make real sense to me and should not be the excpected behavior. You can see the behavior in the codesandbox example for the "File" menu entry.

Expected behavior
Show the menu icon regardless whether the menu entry has childrens or not.

Minimal reproduction of the problem with instructions
Use PanelMenu Component and set the icon property while not setting the items property

Please tell us about your environment:
Tested with Unix/Windows environments

• React version:
  16.12.0

• PrimeReact version:
  3.3.3

• Browser: [all]

• Language: [all]