GLSLNodeBuilder: Fix array texture layer support for filtered sampling

[RenaudRohlinger]

Related issue: #32990

Description
Following #32990 this also fix filtered sampling in the WebGLBackend.

This contribution is funded by Spawn

[github-actions]

📦 Bundle size

Full ESM build, minified and gzipped.

	Before	After	Diff
WebGL	359.14 85.24	359.14 85.24	+0 B +0 B
WebGPU	623.22 173.39	623.31 173.4	+90 B +9 B
WebGPU Nodes	621.8 173.14	621.89 173.15	+90 B +9 B

🌳 Bundle size after tree-shaking

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

	Before	After	Diff
WebGL	490.87 119.65	490.87 119.65	+0 B +0 B
WebGPU	696.79 188.39	696.88 188.4	+90 B +11 B
WebGPU Nodes	645.99 175.78	646.08 175.79	+90 B +11 B