Bump Smithy to 1.60.2 (#4192)

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- [ ] For changes to the smithy-rs codegen or runtime crates, I have
created a changelog entry Markdown file in the `.changelog` directory,
specifying "client," "server," or both in the `applies_to` key.
- [ ] For changes to the AWS SDK, generated SDK code, or SDK runtime
crates, I have created a changelog entry Markdown file in the
`.changelog` directory, specifying "aws-sdk-rust" in the `applies_to`
key.

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Author: ysaito1001

gradle.properties

@@ -15,7 +15,7 @@ smithy.rs.runtime.crate.unstable.version=0.60.6
 kotlin.code.style=official
 # codegen
 smithyGradlePluginVersion=0.9.0
-smithyVersion=1.59.0
+smithyVersion=1.60.2
 allowLocalDeps=false
 # kotlin
 kotlinVersion=1.9.20