Fix minor error in documentation for reflection component (#5698)

Fix a </a-scene> which is out of place.

Author: jgbarah

Diff for: docs/components/reflection.md

@@ -30,8 +30,9 @@ Once the user leaves AR this light may have a different color, intensity and pos
 The example below sets the reflection color to red and use lighting estimation for AR.
 
 ```html
-<a-scene reflection="directionalLight:a-light#dirlight;"></a-scene>
+<a-scene reflection="directionalLight:a-light#dirlight;">
 	<a-light id="dirlight" intensity="1" light="castShadow:true;type:directional" position="1 1 1"></a-light>
+</a-scene>
 ```
 
 ## Properties