Updates package versions in Quick Start docs (reduxjs#1337)

* Updates package versions in Quick Start docs

* Updates versioned docs for v7.1

Author: rszalski

docs/introduction/quick-start.md

@@ -11,7 +11,7 @@ sidebar_label: Quick Start
 
 ## Installation
 
-React Redux 6.x requires **React 16.4 or later.**
+React Redux 7.1 requires **React 16.8.3 or later.**
 
 To use React Redux with your React app:
 

website/versioned_docs/version-7.1/introduction/quick-start.md

@@ -12,7 +12,7 @@ original_id: quick-start
 
 ## Installation
 
-React Redux 6.x requires **React 16.4 or later.**
+React Redux 7.1 requires **React 16.8.3 or later.**
 
 To use React Redux with your React app: