[DataGrid] Add a Selectable function parameter to SelectColumn

[miguelhasse]

Pull Request

📖 Description

This feature introduces the ability to choose if a row can be selected when using SelectColumn.
A typical scenario would be to allow row selection based on the bound item state or a set of conditions.

👩‍💻 Reviewer Notes

A working sample has been added to FluentUI.Demo in the multi-select section.

📑 Test Plan

Unit tests covering the new parameter have been included.

✅ Checklist

General

• I have added tests for my changes.
• I have tested my changes.
• I have updated the project documentation to reflect my changes.
• I have read the CONTRIBUTING documentation and followed the standards for this project.

Component-specific

• I have added a new component
• I have added Unit Tests for my new component
• I have modified an existing component
• I have validated the Unit Tests for an existing component