fix: remove FluentDataGridRow z-index property

[LuohuaRain]

Pull Request

📖 Description

When the z-index of FluentDataGridRow is set to 3, it conflicts with the styles of some components, such as FluentSelect.

Therefore, the z-index property is removed from FluentDataGridRow.

🎫 Issues

👩‍💻 Reviewer Notes

📑 Test Plan

✅ 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 compontent
• I have modified an existing component
• I have validate Unit Tests for an existing component

⏭ Next Steps

[vnbaaij]

The z-index had been given this value for a reason. Please see #744.
A solution for the list to appear above the grid was given in #771. Please confirm that this solution works for you as well. If not, then we can see how we can change this but this PR will not be merged in its current form.

[LuohuaRain]

Thank you for pointing me to issues #744 and #771. I have reviewed the suggested solution in #771 and confirmed that it works for my case as well. Given that the current z-index value has its reasons, I agree that this PR is not needed in its current form. Thanks for your guidance.