WebGPUAttributeUtils: use correct buffer offset for updateRanges

[zonkypop]

Description
Currently when using updateRanges with the WebGPU renderer, the updates are being copied to the start of the buffer.

This PR sets the correct buffer destination offset for: device.queue.writeBuffer, so updateRanges work the same as the WebGLRenderer.

[github-actions]

📦 Bundle size

Full ESM build, minified and gzipped.

	Before	After	Diff
WebGL	336.64 78.39	336.64 78.39	+0 B +0 B
WebGPU	522.6 145.08	522.6 145.09	+2 B +5 B
WebGPU Nodes	522.07 144.98	522.07 144.98	+2 B +4 B

🌳 Bundle size after tree-shaking

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

	Before	After	Diff
WebGL	465.76 112.28	465.76 112.28	+0 B +0 B
WebGPU	593.07 160.7	593.07 160.71	+2 B +5 B
WebGPU Nodes	548.19 150.13	548.2 150.14	+2 B +4 B

[Mugen87]

Do you mind demonstrating the current issue with a fiddle so it is easier for us to reproduce the bug and validate your fix?

Use https://jsfiddle.net/xno7bmw0/ as a start template.

[zonkypop]

Do you mind demonstrating the current issue with a fiddle so it is easier for us to reproduce the bug and validate your fix?

Here's a fiddle: https://jsfiddle.net/zonkypop/0s6u4dac/11/

You can see the difference by changing: forceWebGL: true

Tested on macOS and Linux WebGPU