fix: upgrade smithy-kotlin to pick up fixes for header signing

Author: ianbotsf

.changes/9922940a-efce-4e11-b953-f55c6feb4aef.json

@@ -0,0 +1,5 @@
+{
+    "id": "9922940a-efce-4e11-b953-f55c6feb4aef",
+    "type": "bugfix",
+    "description": "Upgrade **smithy-kotlin** version to pick up fixes for header signing"
+}

gradle/libs.versions.toml

@@ -12,8 +12,8 @@ atomicfu-version = "0.25.0"
 binary-compatibility-validator-version = "0.16.3"
 
 # smithy-kotlin codegen and runtime are versioned separately
-smithy-kotlin-runtime-version = "1.4.1"
-smithy-kotlin-codegen-version = "0.34.1"
+smithy-kotlin-runtime-version = "1.4.2"
+smithy-kotlin-codegen-version = "0.34.2"
 
 # codegen
 smithy-version = "1.53.0"