Retain link in README to stable version

Author: shriyakalakata

README.md

@@ -31,7 +31,7 @@ and various graphical user interface toolkits.
 ## Install
 
 See the [install
-documentation](https://matplotlib.org/stable/install/index.html),
+documentation](https://matplotlib.org/stable/users/installing/index.html),
 which is generated from `/doc/install/index.rst`
 
 ## Contribute