Refactor Inserter Button to functional component

[coderGtm]

What?

See #22890
This PR refactors InserterButton's MenuItem from class based component syntax to newer functional component syntax.

Why?

Class based components are no longer the recommended approach & instead functional syntax with hooks is more recommended.
The code becomes more readable & easier to maintain.

How?

This version uses a functional component and the useCallback hook for the onPress handler. All props and logic are preserved in the functional syntax.

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