Make React.memo documentation more clear (#2762)

* Make React.memo documentation more clear

* Update reference-react.md

Co-authored-by: Sunil Pai <threepointone@fb.com>

content/docs/reference-react.md

@@ -128,7 +128,7 @@ const MyComponent = React.memo(function MyComponent(props) {
 
 If your function component renders the same result given the same props, you can wrap it in a call to `React.memo` for a performance boost in some cases by memoizing the result. This means that React will skip rendering the component, and reuse the last rendered result.
 
-`React.memo` only affects props changes. If your function component wrapped in `React.memo` has a [`useState`](/docs/hooks-state.html) or [`useContext`](/docs/hooks-reference.html#usecontext) Hook in its implementation, it will still rerender when state or context change.
+`React.memo` only checks for prop changes. If your function component wrapped in `React.memo` has a [`useState`](/docs/hooks-state.html) or [`useContext`](/docs/hooks-reference.html#usecontext) Hook in its implementation, it will still rerender when state or context change.
 
 By default it will only shallowly compare complex objects in the props object. If you want control over the comparison, you can also provide a custom comparison function as the second argument.