Running aarch64 codebuild image on a x86_64 machine

I have a Lambda function with `arm64` architecture running Python 3.9, which is deployed to our production environment using CodePipeline using the [amazonlinux2-aarch64-standard:2.0](https://github.com/aws/aws-codebuild-docker-images/blob/master/al2/aarch64/standard/2.0) image. This all works fine. By using this image, `aarch64` versions of the python dependencies for the Lambda can be installed using `buildspec.yml` and tools like `pytest` can run in an `aarch64` environment during the build process.

The problem arises when building and deploying a copy of the lambda for development purposes by building locally using the [`codebuild_build.sh` script](https://github.com/aws/aws-codebuild-docker-images/blob/c32d02967166621d948166e642b1b621ca0038cb/local_builds/README.md). Since my machine has `x86_64` architecture, this fails (logs below).

**Describe the issue**
Unable to run `public.ecr.aws/codebuild/amazonlinux2-x86_64-standard:4.0` codebuild image using `codebuild_build.sh` on an `x86_64` machine.

**To Reproduce**
Steps to reproduce the behavior:
1. pull `amazonlinux2-aarch64-standard:2.0` docker image on an x86_64 machine
```
docker pull public.ecr.aws/codebuild/amazonlinux2-aarch64-standard:2.0
```
2. run `./build_scripts/local/codebuild_build.sh -i aws/codebuild/amazonlinux2-aarch64-standard:2.0 -a tmp/`

**Expected behavior**
Build should run without issue.

**Logs**
```
Build Command:

docker run -it -v /var/run/docker.sock:/var/run/docker.sock -e "IMAGE_NAME=aws/codebuild/amazonlinux2-aarch64-standard:2.0" -e "ARTIFACTS=/home/dhospital/work/feature-flags-service/tmp/" -e "SOURCE=/home/dhospital/work/feature-flags-service" -e "INITIATOR=dhospital" public.ecr.aws/codebuild/local-builds:latest

Removing agent-resources_build_1 ... done
Removing agent-resources_agent_1 ... done
Removing network agent-resources_default
Removing volume agent-resources_source_volume
Removing volume agent-resources_user_volume
Creating network "agent-resources_default" with the default driver
Creating volume "agent-resources_source_volume" with local driver
Creating volume "agent-resources_user_volume" with local driver
Creating agent-resources_agent_1 ... done
Creating agent-resources_build_1 ... done
Attaching to agent-resources_agent_1, agent-resources_build_1
build_1 | exec /usr/bin/sh: exec format error
agent-resources_build_1 exited with code 1
Stopping agent-resources_agent_1 ... done
Aborting on container exit...
```

**Platform (please complete the following information):**
- OS: Linux x86