Examples: Clean up. (#29157)

examples/jsm/objects/SkyMesh.js

@@ -175,7 +175,6 @@ class SkyMesh extends Mesh {
 
 		} )();
 
-		material.normals = false;
 		material.side = BackSide;
 		material.depthWrite = false;
 

examples/jsm/objects/Water2Mesh.js

@@ -24,7 +24,6 @@ class WaterMesh extends Mesh {
 
 		this.isWater = true;
 
-		material.normals = false;
 		material.fragmentNode = new WaterNode( options, this );
 
 	}

examples/jsm/objects/WaterMesh.js

@@ -93,7 +93,6 @@ class WaterMesh extends Mesh {
 
 		} )();
 
-		material.normals = false;
 		material.fragmentNode = fragmentNode;
 
 	}