Version 3.2.3

Changelog-Exempt: Changelog is already correct.
Change-Id: I1f2b7bf70328d8387f37f45a5a53fc4920e90342
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/340000
Commit-Queue: Alexander Thomas <athom@google.com>
Reviewed-by: William Hesse <whesse@google.com>

Author: athomas

tools/VERSION

@@ -26,6 +26,6 @@
 CHANNEL stable
 MAJOR 3
 MINOR 2
-PATCH 2
+PATCH 3
 PRERELEASE 0
 PRERELEASE_PATCH 0