fix: api key identity resolver config codegen

[nated0g]

Issue #, if available:

Description of changes:

self.api_key_identity_resolver was never being set on the generated Config, only a local api_key_identity_resolver was being set (and then never being used).

This was leading to an error when trying to make requests to a service with api key auth.

'Config' object has no attribute 'api_key_identity_resolver'

---

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[jonathan343]

This change looks good to me! Gonna drop some testing notes below:

We will create a test directory called test_dir with the following structure:

.
├── models
│   └── model.smithy
└── smithy-build.json

Generate A Test Service w/ httpApiKeyAuth Trait

$version: "2.0"

namespace com.example
use aws.protocols#restJson1

/// Echoes input
@restJson1
@httpApiKeyAuth(name: "X-Api-Key", in: "header")
service EchoService {
    version: "2006-03-01"
    operations: [EchoMessage]
}

@http(uri: "/echo", method: "POST")
operation EchoMessage {
    input := {
        @httpHeader("x-echo-message")
        message: String
    }
    output := {
        message: String
    }
}

Create smithy-build.json File

{
    "version": "1.0",
    "sources": ["models"],
    "maven": {
        "dependencies": [
            "software.amazon.smithy:smithy-model:[1.54.0,2.0)",
            "software.amazon.smithy:smithy-aws-traits:[1.54.0,2.0)",
            "software.amazon.smithy.python.codegen.aws:core:0.0.1"
        ]
    },
    "projections": {
        "client": {
            "plugins": {
                "python-client-codegen": {
                    "service": "com.example#EchoService",
                    "module": "echo",
                    "moduleVersion": "0.0.1"
                }
            }
        }
    }
}

Build Code Generator

uv venv 
. .venv/bin/activate

make install
make build-java
./gradlew publishToMavenLocal

cd ../test_dir
smithy build

Install Echo Client

cd build/smithy/client/python-client-codegen
uv pip install .

Run the following script

import asyncio

from echo.client import EchoService
from echo.config import Config
from echo.models import EchoMessageInput


import logging 
logging.basicConfig(level=logging.DEBUG)

async def main() -> None:
    client = EchoService(Config(endpoint_uri="https://example.com/", api_key="testing123123"))
    response = await client.echo_message(EchoMessageInput(message="spam"))
    print(response.message)


if __name__ == "__main__":
    asyncio.run(main())

Verify Auth Header Sent

DEBUG:smithy_core.aio.client:Sending request HTTPRequest(destination=URI(scheme='https', username=None, password=None, host='example.com', port=None, path='/echo', query='', fragment=None), method='POST', fields=Fields(OrderedDict({'x-echo-message': Field(name='x-echo-message', value=['spam'], kind=<FieldPosition.HEADER: 0>), 'user-agent': Field(name='User-Agent', value=['aws-sdk-python/0.0.3 md/smithy-core#0.0.2 md/awscrt#0.26.1 ua/2.1 api/EchoService#0.0.1 os/macos#24.6.0 md/arch#arm64 lang/python#3.12.11 md/pyimpl#CPython'], kind=<FieldPosition.HEADER: 0>), 'x-api-key': Field(name='X-Api-Key', value=['testing123123'], kind=<FieldPosition.HEADER: 0>)})))

[jonathan343]

LGTM!