[Docs] Fixes for feature_rgblight.md (#8514)

* remove extra comma that breaks the RGBLight Layers example

* linting

- use four spaces instead of tabs for indenting
- remove trailing spaces

docs/feature_rgblight.md

@@ -191,7 +191,7 @@ const rgblight_segment_t PROGMEM my_layer1_layer[] = RGBLIGHT_LAYER_SEGMENTS(
 );
 // Light LEDs 11 & 12 in purple when keyboard layer 2 is active
 const rgblight_segment_t PROGMEM my_layer2_layer[] = RGBLIGHT_LAYER_SEGMENTS(
-	{11, 2, HSV_PURPLE}, 
+    {11, 2, HSV_PURPLE}
 );
 // etc..
 ```