[mesh][ui] Changing settings for 2D Contour color ramp shader shows confusing widgets

[DelazJ]

In mesh layer 3D properties, switch the rendering style to 2D contour color ramp shader
Then collapse the "rendering color settings" group and expand it again: you got all the widgets in the group visible

and I also get the same in the 3D Map configuration dialog, using "single color" for mesh terrain

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