ecr-login credential helper doesn't pass through AWS variables

[ollypom]

Describe the bug
If a user is using the ecr-login credential helper with Finch, AWS environment variables set outside of the VM are not passed through into the VM.

For example, lets say the user sets export AWS_PROFILE=personal in there terminal, expecting the credential helper to use that profile (as it would on Linux), however these variables are not passed through to nerdctl in the VM so finch push / pull will fail. My assumption is that Finch will therefore always use the default AWS credentials found in the /Users/<username>/.aws/config.

This may be fixed by #510

Steps to reproduce

$ export AWS_ACCOUNT_ID=111222333444
$ export AWS_REGION=eu-west-1
$ export AWS_PROFILE=personal

$ finch tag busybox:latest $AWS_ACCOUNT_ID.dkr.ecr.$AWS_REGION.amazonaws.com/nginx:latest
$ finch push --platform linux/arm64 $AWS_ACCOUNT_ID.dkr.ecr.$AWS_REGION.amazonaws.com/nginx:latest
FATA[0000] unexpected status from HEAD request to https://111222333444.dkr.ecr.eu-west-1.amazonaws.com/v2/nginx/blobs/sha256:fc9db2894f4e4b8c296b8c9dab7e18a6e78de700d21bc0cfaf5c78484226db9c: 403 Forbidden 
FATA[0000] exit status 1 

Expected behavior
The AWS variables to be passed through into the VM.

Workarounds
Don't use the credential helper and do a manual finch login when you do not want to use the default AWS credentials.

$ export AWS_ACCOUNT_ID=111222333444
$ export AWS_REGION=eu-west-1
$ export AWS_PROFILE=personal

$ aws ecr get-login-password --region $AWS_REGION | finch login --username AWS --password-stdin $AWS_ACCOUNT_ID.dkr.ecr.$AWS_REGION.amazonaws.com
WARNING: Your password will be stored unencrypted in /Users/<username>/.finch/config.json.
Configure a credential helper to remove this warning. See
https://docs.docker.com/engine/reference/commandline/login/#credentials-store

Login Succeeded

Or I suppose you could set the environment variables in /Applications/Finch/os/finch.yaml if you know the AWS variables are not going to be changed often.

To help debug the issue as quickly as possible, we recommend generating a support bundle with finch support-bundle generate and attaching it to this issue. This packages all Finch-related configs and logs into one file.