WebGPURenderer: fix renderGroup.needs update logic

[aardgoose]

Related issue: #29386

Minor breakage from change in needsUpdate logic.

Note: the performance examples are now broken with the fallback renderer, presumably from the lack of shared UBOs. I'll take a look at that. (only one object in the renderBundle rotates, and only some of the game model objects rotate)

[github-actions]

📦 Bundle size

Full ESM build, minified and gzipped.

	Before	After	Diff
WebGL	685.83 169.75	685.83 169.75	+0 B +0 B
WebGPU	832.14 222.98	832.13 222.98	-5 B +1 B
WebGPU Nodes	831.65 222.86	831.64 222.86	-5 B +2 B

🌳 Bundle size after tree-shaking

Minimal build including a renderer, camera, empty scene, and dependencies.

	Before	After	Diff
WebGL	462.42 111.53	462.42 111.53	+0 B +0 B
WebGPU	529.9 142.75	529.89 142.75	-5 B +4 B
WebGPU Nodes	486.56 132.61	486.55 132.62	-5 B +4 B

[sunag]

presumably from the lack of shared UBOs.

I also suspect it's the same thing.

[aardgoose]

Confirmed, got a prototype working now.