Fix incorrect closing tags (#85)

Author: kantbtrue

apps/docs/public/docs/components/slider.mdx

@@ -25,7 +25,7 @@ For more advanced usage, you can use the `Slider.Root` component to compose your
         <Slider.Range />
     </Slider.Track>
     <Slider.Thumb />
-</Avatar.Root>
+</Slider.Root>
 ```
 
 ### API Reference
@@ -176,4 +176,4 @@ Controlled component:
 
 Playground:
 
-<PreviewComponent name="slider/example-5" />
+<PreviewComponent name="slider/example-5" />