[Visual] VisualGrid: do not update bbox

[EulalieCoevoet]

Problem

We use the VisualGrid to understand and visualize the scene distance unit and to quickly measure distances when analyzing a simulation. For aesthetic purposes, our grids are set to be n times larger than the scene bounding box.
Currently, the VisualGrid component contributes to the scene bounding box, which I would argue should not be the case in general.

In this PR

Removes the bbox update.
If you prefer, I can add a boolean to choose whether to update the bbox.

Screenshot

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• it builds with SUCCESS for all platforms on the CI.
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• it does not generate new scene test failures.
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[damienmarchal]

Thank for the PR.

I'm not sure about the fix, I have impression that the expected behavior for any VisualXXX object (like a visual model) is to update the bbox.

I wonder if the problem you are fixing is not a consequence of using scene component to implement viewer's Gizmos. If this is the case, then these visual helper shouldn't be part of the scene but should be an utility object of the BaseViewer. To control the rendering of Gizmos of the viewer's should have binding to python or scene component, changing the viewer properties (as done in ViewerSetting).

I agree that what I'm suggesting would be a more drastic move compared to what you are proposing but it would make thing much simpler as it would apply for every UI gizmo's.