Implement Display Trait for DateTime

[HakanVardarr]

Motivation and Context

It implements Display trait For DateTime

#3161

Description

I implemented Display trait for DateTime

Testing

I used this test

    fn test_display_formatting() {
        // Create a DateTime instance for testing
        let datetime = DateTime {
            seconds: 1636761600, // Example timestamp (replace with your actual timestamp)
            subsecond_nanos: 123456789, // Example subsecond nanos (replace with your actual value)
        };

        // Expected RFC-3339 formatted string
        let expected = "2021-11-13T00:00:00.123456789Z";

        // Format the DateTime using Display trait
        let formatted = format!("{}", datetime);

        // Assert that the formatted string matches the expected result
        assert_eq!(formatted, expected);
    }

Checklist

• I have updated CHANGELOG.next.toml if I made changes to the smithy-rs codegen or runtime crates
• I have updated CHANGELOG.next.toml if I made changes to the AWS SDK, generated SDK code, or SDK runtime crates

---

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

[HakanVardarr]

I don't know if I need to any updates on CHANGELOG.next.toml so I didn't do anything with it. If it is necessary can you help me on that?

[rcoh]

instead of using chrono, we should use the date time support already built into datetime: https://docs.rs/aws-smithy-types/latest/aws_smithy_types/date_time/struct.DateTime.html#method.fmt

make sure to also remove the chrono dependency

[rcoh]

we'll also need at least one test

[jdisanti]

I don't know if I need to any updates on CHANGELOG.next.toml so I didn't do anything with it. If it is necessary can you help me on that?

You should add the following:

[[aws-sdk-rust]]
message = "Add `Display` impl for `DateTime`."
references = ["smithy-rs#3183"]
meta = { "breaking" = false, "tada" = true, "bug" = false }
author = "HakanVardarr"

[[smithy-rs]]
message = "Add `Display` impl for `DateTime`."
references = ["smithy-rs#3183"]
meta = { "breaking" = false, "tada" = true, "bug" = false, "target" = "all" }
author = "HakanVardarr"

[HakanVardarr]

Is this better?

[rcoh]

Looks good!