Fix grammar error in the fragments page of docs (#4267)

Summary:
> The avoid these and many other problems, we can move the data requirements for the Story component into Story.tsx.

The -> To

Pull Request resolved: #4267

Reviewed By: alunyov

Differential Revision: D44503263

Pulled By: rbalicki2

fbshipit-source-id: 74b52d35b0f6d1c5047c390205515d364007e06a

website/docs/tutorial/fragments-1.md

@@ -65,7 +65,7 @@ The date should now appear. And thanks to GraphQL, we didn't have to write and d
 
 But if you think about it, why should you have had to modify `Newsfeed.tsx`? Shouldn’t React components be self-contained? Why should Newsfeed care about the specific data required by Story? What if the data was required by some child component of Story way down in the hierarchy? What if it was a component that was used in many different places? Then we would have to modify many components whenever its data requirements changed.
 
-The avoid these and many other problems, we can move the data requirements for the Story component into `Story.tsx`.
+To avoid these and many other problems, we can move the data requirements for the Story component into `Story.tsx`.
 
 We do this by splitting off `Story`’s data requirements into a *fragment* defined in `Story.tsx`. Fragments are separate pieces of GraphQL that the Relay compiler stitches together into complete queries. They allow each component to define its own data requirements, without paying the cost at runtime of each component running its own queries.