[Bug]: Fix cargo audit issue on chrono in Rust examples

[ysaito1001]

Expected behavior

Examples should be error-free when run against cargo audit. There has been a PR in aws-sdk-rust that attempts to remove cargo audit's --ignore flags for RUSTSEC-2020-0071 and RUSTSEC-2020-0159. When cargo audit runs as part of CI for the PR, the check should pass, saying that no issues have been found.

Actual behavior

In the said PR, the following examples have been reported in CI to depend upon the chrono crate that can cause potential segfaults (per RUSTSEC-2020-0071). A cargo dependency tree leading to the issue looks as follows:

Dependency tree:
time 0.1.45
└── chrono 0.4.23
    ├── cognitoidentity-code-examples 0.1.0
    └── aws-smithy-types-convert 0.52.0
        ├── sitewise-code-examples 0.1.0
        ├── sagemaker-code-examples 0.1.0
        ├── cognitosync-code-examples 0.1.0
        ├── cognitoidentityprovider-code-examples 0.1.0
        ├── cognitoidentity-code-examples 0.1.0
        └── apigateway-code-examples 0.1.0

These examples should update their dependencies so that they do not depend on the chrono crate. An example fix can be found here. Ensure that cargo audit runs in CI so that the check runs against all of the submitted PRs.

This issue is currently blocking the PR to be merged in the main branch.

Steps to reproduce

1. Clone the aws-doc-sdk-examples
2. `cd` into `rust_dev_preview`
3. Run `rm Cargo.lock; cargo audit`, which should generate the report that appeared in CI

Logs / stacktrace (if applicable)

No response

Which SDK were you using?

Rust

Which OS were you using?

macOS

SDK version

No response

OS version

No response

[brmur]

@DavidSouther to investigate

[github-actions]

Marked stale by the Shirriff. Notifying @awsdocs/aws-sdk-docs-code-maintainers

[DavidSouther]

There's a few crates, including SDK crates, that depend on Chrono 0.4.23 (the latest). This depends on a chrono update (or migrating off chrono).

Blocked on chronotope/chrono#602
and awslabs/aws-sdk-rust#646