Incorrect window close button style

[Roel84]

Place your issue description here.

The background color of the window's close button is incorrect when hovered over:

It seems that this issue was already fixed with a8bf790 but didn't make in the v10.1.0 release.

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Environment

• Fluent.Ribbon v10.1.0
• Windows 10
• .NET Framework 4.8

[batzen]

This is fixed in v11 and i don't plan to release another 10.X version.
Will try to release v11 during October.