[release] Update changelog for 2.18.2

Bug: #50052
Change-Id: I1d9aedac81b2fdb05f04a0246d1088ffa66192ef
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/261300
Reviewed-by: Alexander Thomas <athom@google.com>

CHANGELOG.md

@@ -152,7 +152,10 @@ Updated the Linter to `1.28.0`, which includes changes that
 
 ## 2.18.2 - 2022-09-28
 
-This is a patch release that fixes incorrect behavior in `Uri.parse`.
+This is a patch release that:
+
+- fixes incorrect behavior in `Uri.parse`.
+- fixes a compiler crash (issue [#50052][]).
 
 ### Libraries
 
@@ -165,6 +168,8 @@ This is a patch release that fixes incorrect behavior in `Uri.parse`.
   The Dart `Uri` class is still not an implementation of the same standard
   as the browser's `URL` implementation.
 
+[#50052]: https://github.com/dart-lang/sdk/issues/50052
+
 ## 2.18.1 - 2022-09-14
 
 This is a patch release that fixes a crash caused by incorrect type inference