AWS STS Documentation incorrect. Suggests Credentials meet provideCredentials crate

### Describe the bug

Currently on the aws-sdk-sts documentation for the [Credentials](https://docs.rs/aws-sdk-sts/latest/aws_sdk_sts/struct.Credentials.html) struct, it shows an [impl](https://docs.rs/aws-sdk-sts/latest/aws_sdk_sts/struct.Credentials.html#impl-ProvideCredentials-for-Credentials) for the aws_credentials_types [ProvideCredentials](https://docs.rs/aws-credential-types/0.54.1/aws_credential_types/provider/trait.ProvideCredentials.html) trait. However it appears that the modeled version from STS does not implement this trait and is referencing the [Credentials struct in aws_credentials_types](https://docs.rs/aws-credential-types/0.54.1/aws_credential_types/struct.Credentials.html).

### Expected Behavior

I'd expect the STS modeled credentials to either implement ProvideCredentials or not document this as a trait implementation.

### Current Behavior

The docs show the ProvideCredentials trait is implemented, but it can't compile

### Reproduction Steps

```
async fn get_credentials_helper() -> Box

Start with the aws_sdk_sts::Credentials documentation and compare its displayed ProvideCredentials implementation with aws_credential_types::Credentials and the trait. Run the v0.54.1/v0.24.0 reproduction to confirm the compile failure. Done means the documentation accurately reflects whether the modeled STS credentials implement ProvideCredentials.

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