Add 2.14.1 to changelog

Also add release dates for 2.14.0 and 2.14.1

Fixes https://github.com/dart-lang/sdk/issues/47178

Closes https://github.com/dart-lang/sdk/pull/47182
https://github.com/dart-lang/sdk/pull/47182

GitOrigin-RevId: 0830cdc0bb4546a95a13458aa93134bb646e0dad
Change-Id: Ia7909f5cfb57d5a037d169889c3b6a1520cfb843
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/213060
Reviewed-by: Alexander Thomas <athom@google.com>
diff --git a/CHANGELOG.md b/CHANGELOG.md
index ffd3eec..7c0c92b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -131,7 +131,12 @@
 - improves performance for `annotate_overrides`, `prefer_contains`, and
   `prefer_void_to_null`.
 
-## 2.14.0
+## 2.14.1 - 2021-09-09
+
+- Fixed an issue specific to the macOS ARM64 (Apple Silicon) SDK, where the Dart
+  commandline tools did not have the expected startup performance.
+
+## 2.14.0 - 2021-09-09
 
 ### Language