Docs: Remove Dead Example

docs/api/en/materials/SpriteMaterial.html

@@ -27,7 +27,6 @@
 		<h2>Examples</h2>
 		<p>
 			[example:webgl_sprites webGL / sprites]<br />
-			[example:software_sandbox software / sandbox]<br />
 			[example:svg_sandbox svg / sandbox]<br />
 			[example:webgl_materials_cubemap_dynamic webgl / materials / cubemap / dynamic]
 		</p>