Remove AspireFluentDataGridHeaderCell

[JamesNK]

Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

FluentUI has been updated to support the features that AspireFluentDataGridHeaderCell provides. Investigate removing our implementation and using the built in one.

Expected Behavior

No response

Steps To Reproduce

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Exceptions (if any)

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.NET Version info

No response

Anything else?

No response

[JamesNK]

Done in #6840