Hide multiselect panel on living by TAB key

[adopilot]

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[x] feature request => Please check if request is not on the roadmap already https://github.com/primefaces/primeng/wiki/Roadmap
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Current behavior
Multi select (p-multiSelect) control has decent keyboard pickup behavior (mouse less operation).
User can pull list by Alt+down, Select items by enter (it will be nice if we clod also add space key as item selector key stroke).
The problem for users which trying to fill form without mouse is when they leave multiselect control by TAB key, control do not accept new value and it's panel remain open.

Expected behavior
Select items by space key (optional)
Commit (set value) after control lose focus (onBlur)
Commit (set value) by enter key and hide panel

You can try on multiSelect reproduce this.
Start editing first multi select control (open panel by Key+DOWN or type something in search box) use TAB key to move to next contol.