Update WebGLRenderer.js

Fix typo.

src/renderers/WebGLRenderer.js

@@ -1419,7 +1419,7 @@ class WebGLRenderer {
 					type: ( extensions.has( 'EXT_color_buffer_half_float' ) || extensions.has( 'EXT_color_buffer_float' ) ) ? HalfFloatType : UnsignedByteType,
 					minFilter: LinearMipmapLinearFilter,
 					samples: 4,
-					stencil: stencil
+					stencilBuffer: stencil
 				} );
 
 				// debug