Correct removing duplicate positions from WallGeometry

[hpinkos]

Fixes #8842

WallGeometry was missing a call to arrayRemoveDuplicates that we created to standardize the epsilon distance at which to remove duplicate positions.

Also updated the lat/lon epsilon check to use EPSILON10. We initially undershot with EPSILON6, then #1483 overshot and changed it to EPSILON14, but EPSILON10 is what we've standardized on in arrayRemoveDuplicates and our other geometry duplicate check functions.

[cesium-concierge]

Thanks for the pull request @hpinkos!

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[mramato]

Thanks!