a typo (#228)

exercises/04.context/README.mdx

@@ -51,7 +51,7 @@ components that need to share the state or perhaps there's a router involved and
 you aren't the one rendering the components and don't have an easy way to pass
 props down.
 
-Another situation where you would use this is if you wanted to implicitely share
+Another situation where you would use this is if you wanted to implicitly share
 state between components so consumers of those components can use them without
 having to know about the state. This is a pattern known as "Compound Components"
 and we'll learn more about that in the Compound Components exercise of the