Use content classificationType rather than tileset classificationType

[lilleyse]

Batched3DModel3DTileContent should be using its own internal classificationType rather than tileset.classificationType. This was missed in one spot in #9398.

In this code path content._classificationType will be the same as tileset.classificationType so this is just a cosmetic fix.

I confirmed that Photogrammetry Classification still works.

[cesium-concierge]

Thanks for the pull request @lilleyse!

• ✔️ Signed CLA found.
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Reviewers, don't forget to make sure that:

• Cesium Viewer works.
• Works in 2D/CV.
• Works (or fails gracefully) in IE11.

[ebogo1]

Looks good, thanks @lilleyse! I'll merge once CI passes.