[DataGrid] Add SingleSticky selection mode

[hml-coder]

Pull Request

📖 Description

Added SingleSticky selection mode to FluentDataGrid to retain selection when the same row is clicked again.

🎫 Issues

Fix #3138

👩‍💻 Reviewer Notes

📑 Test Plan

Duplicated all tests for Single selection mode.

✅ 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

⏭ Next Steps

[hml-coder]

@microsoft-github-policy-service agree

[hml-coder]

Thanks @vnbaaij and @dvoituron for approving this. I'm porting vb6, winforms and wpf apps to Blazor and this was logged as a bug internally because the datagrid selections were being lost.

Is there anything I need to correct because there a "failed" indicator on the main project page?