Shaders: Clean up (#33133)

src/renderers/shaders/ShaderChunk/premultiplied_alpha_fragment.glsl.js

@@ -1,7 +1,6 @@
 export default /* glsl */`
 #ifdef PREMULTIPLIED_ALPHA
 
-	// Get normal blending with premultipled, use with CustomBlending, OneFactor, OneMinusSrcAlphaFactor, AddEquation.
 	gl_FragColor.rgb *= gl_FragColor.a;
 
 #endif