Capitalize Components in index.md

Author: Dextheking1

src/content/learn/index.md

@@ -23,7 +23,7 @@ Welcome to the React documentation! This page will give you an introduction to 8
 
 React apps are made out of *components*. A component is a piece of the UI (user interface) that has its own logic and appearance. A component can be as small as a button, or as large as an entire page.
 
-React components are JavaScript functions that return markup:
+React Components are JavaScript functions that return markup:
 
 ```js
 function MyButton() {