[MultiSelect2] allow to create multiple items

[ZeRego]

Environment

• Package version(s): 4.2.0
• Browser and OS versions:

Feature request

Multi select should allow the same behaviour we have in the tag input component where we can create multiple values at once. Multi select doesn't need to implement the same behaviour, it just needs to support creating multiple items at once.

Existing typing

createNewItemFromQuery | undefined \| (query: string) => T

Proposed typing

createNewItemFromQuery | undefined \| (query: string) => T | T[]

Examples

How tag input works:

How multi select currently works

I would like to split the input by comma and add both test1 and hello as new values.

[adidahiya]

sounds like a good feature request. accepting PRs ✅