Upgrade trimesh requirement to 4.*

[lucas-flexcompute]

Trimesh 4.* is not backwards compatible with 3.* (see #1538, for example), but gdsfactory requires trimesh >= 4 already.
It would be good to look into upgrading the requirement on our side.

[tylerflex]

hey Lucas, could you assign someone? also maybe give it a priority and size in the Tidy3D tracking section so we can rank it among our other issues for importance, thanks.

[lucas-flexcompute]

I can assign myself because of the transformations, but I won't be able to look into this for a while. If we want to increase the priority here, maybe someone else who's used trimesh could take a look. @weiliangjin2021, how's your plate now?

[weiliangjin2021]

Probably @caseyflex as he implemented this part?

[caseyflex]

yeah I can take this. Do we want it as a patch for 2.6 or in 2.7? @tylerflex

[tylerflex]

Thanks, 2.7 should be fine.