Amazon DynamoDB Accelerator (DAX) is not working

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### What is the problem?

Hello all,

I am trying to use DAX, and I have the following problems.

I try to connect in this way.

```
let dax_endpoint = std::env::var("DAX_ENDPOINT").expect("DAX_ENDPOINT must be set");
let dynamodb_dax_config = aws_sdk_dynamodb::config::Builder::from(&config)
.endpoint_resolver(
Endpoint::immutable(dax_endpoint.parse().unwrap()),
)
.build();

let dynamodb_client = aws_sdk_dynamodb::Client::from_conf(dynamodb_dax_config);
```

Lambda Env Variables:
DAX_ENDPOINT: ****DAX_DOMAIN****:8111

I get this error:

```
thread 'main' panicked at 'scheme must be provided', /Users/xxx/.cargo/registry/src/github.com-1ecc6299db9ec823/aws-smithy-http-0.38.0/src/endpoint.rs:97:50
```

If I add the schema and I tried:
- dax://
- http://
- https://

I get time out:

```
INFO send_operation{operation="Query" service="dynamodb"}:provide_credentials{provider=default_chain}: aws_config::meta::credentials::chain: loaded credentials provider=Environment

error TimeoutError(RequestTimeoutError { kind: "API call (all attempts including retries)", duration: 5s })
```

I have tried this Node example:
https://github.com/aws-samples/amazon-dax-lambda-nodejs-sample/blob/master/template.yaml

My Rust Lambda is in the same security group and subnets of the example run in Node.

If you need more, please let me know.

Dan

### Version

v0.8.0

### Platform

Lambda arm64

### AWS Services

_No response_

### Description

_No response_

### Logs

_No response_

Start with the aws_sdk_dynamodb::config::Builder and Endpoint::immutable calls in the report, then compare them with the linked Node Lambda sample's template.yaml and the aws-smithy-http endpoint.rs error. Reproduce the scheme failure and subsequent timeout in Lambda arm64 using the stated subnets and security group; done means the DAX connection behavior and required endpoint configuration are identified.

Written by the indexing model from the issue text.