BufferGeometry: fix clone index data copy

[s-rigaud]

Description

Not sure about what was the expected behavior and how data should store the index but the clone method inside BufferAttribute does not take any argument (same for subtypes of BufferAttribute).

[github-actions]

📦 Bundle size

Full ESM build, minified and gzipped.

	Before	After	Diff
WebGL	336.02 78.26	336.02 78.26	+0 B +0 B
WebGPU	523.84 145.45	523.84 145.45	+0 B +0 B
WebGPU Nodes	523.31 145.34	523.31 145.34	+0 B +0 B

🌳 Bundle size after tree-shaking

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

	Before	After	Diff
WebGL	465.06 112.14	465.06 112.14	-1 B -1 B
WebGPU	594.24 161.05	594.24 161.05	-1 B -2 B
WebGPU Nodes	549.37 150.49	549.37 150.48	-1 B -1 B