chore: release 0.21.3

Author: aws-sdk-kotlin-ci

.changes/a646a910-2f13-4231-aa51-a5feb2e335a2.json

@@ -1,5 +1,14 @@
 # Changelog
 
+## [0.21.3] - 06/19/2023
+
+### Features
+* [#718](https://github.com/awslabs/smithy-kotlin/issues/718) Support Smithy default trait
+
+### Fixes
+* [#867](https://github.com/awslabs/smithy-kotlin/issues/867) Add fully qualified name hint for collection types
+* [#828](https://github.com/awslabs/smithy-kotlin/issues/828) Use correct precedence order for determining restJson error codes
+
 ## [0.21.2] - 06/08/2023
 
 ### Fixes

.changes/c641c1f7-0758-49d2-8dbd-e375853143c7.json

@@ -6,7 +6,7 @@ kotlin.native.ignoreDisabledTargets=true
 kotlin.mpp.enableCompatibilityMetadataVariant=true
 
 # SDK
-sdkVersion=0.21.3-SNAPSHOT
+sdkVersion=0.21.3
 
 # kotlin
 kotlinVersion=1.8.10