prep changelog for 4.7.1 (#2352)

Co-authored-by: Dan Rosenthal <[email protected]>

Author: tmlayton

CHANGELOG.md

@@ -8,6 +8,12 @@ The format is based on [these versioning and changelog guidelines](https://git.i
 
 ---
 
+## 4.7.1 - 2019-10-23
+
+### Bug fixes
+
+- Fixed a bug with `Button` which caused infinite layout and high CPU load in Safari, related to [WebKit Bug 194332](https://bugs.webkit.org/show_bug.cgi?id=194332) ([#2350](https://github.com/Shopify/polaris-react/pull/2350))
+
 ## 4.7.0 - 2019-10-22
 
 ### Enhancements

UNRELEASED.md

@@ -12,8 +12,6 @@ Use [the changelog guidelines](https://git.io/polaris-changelog-guidelines) to f
 
 ### Bug fixes
 
-- Fixed a bug with `Button` which caused infinite layout and high CPU load in Safari, related to [WebKit Bug 194332](https://bugs.webkit.org/show_bug.cgi?id=194332) ([#2350](https://github.com/Shopify/polaris-react/pull/2350))
-
 ### Documentation
 
 ### Development workflow