build(deps): bump aws-smithy-runtime from 1.1.8 to 1.2.1

Bumps [aws-smithy-runtime](https://github.com/smithy-lang/smithy-rs) from 1.1.8 to 1.2.1.
- [Release notes](https://github.com/smithy-lang/smithy-rs/releases)
- [Changelog](https://github.com/smithy-lang/smithy-rs/blob/main/CHANGELOG.md)
- [Commits](https://github.com/smithy-lang/smithy-rs/commits)

---
updated-dependencies:
- dependency-name: aws-smithy-runtime
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Cargo.toml

@@ -5,7 +5,7 @@ members = ["crates/esthri", "crates/esthri-internals", "crates/esthri-cli", "cra
 aws-sdk-s3 = "1.21.0"
 aws-types = "1.1.8"
 aws-config = { version = "1.1.9", features = ["behavior-version-latest"]}
-aws-smithy-runtime = "1.1.8"
+aws-smithy-runtime = "1.2.1"
 hyper = "0.14.28" # hyper 0.14 is the version used in the aws-smithy-runtime api. Can't upgrade to "1" until smithy-runtime does