Move using-native-tls-instead-of-rustls to smithy-rs (#2423)

* Move using-native-tls-instead-of-rustls to smithy-rs

This commit adds the test `using-native-tls-instead-of-rustls` to
`smithy-rs` that was originally in the `aws-doc-sdk-examples`.
The test is more useful to be in `smithy-rs` because it can catch
a test failure early prior to cutting a release.

* Fix Copyright header

* Update aws/sdk/integration-tests/using-native-tls-instead-of-rustls/tests/no-rustls-in-dependency.rs

Co-authored-by: Zelda Hessler <zhessler@amazon.com>

* Update aws/sdk/integration-tests/using-native-tls-instead-of-rustls/tests/no-rustls-in-dependency.rs

Co-authored-by: Zelda Hessler <zhessler@amazon.com>

* Update Cargo.toml

This commit addresses
https://github.com/awslabs/smithy-rs/pull/2423#discussion_r1123289399
https://github.com/awslabs/smithy-rs/pull/2423#discussion_r1123291290



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Co-authored-by: Yuki Saito <awsaito@amazon.com>
Co-authored-by: Zelda Hessler <zhessler@amazon.com>