debug lambda using private docker registry, --build-image

I'm struggling to start a debug session of a local lambda function. I've added a debug configuration and added the following launch config:
```
"launch": {
"configurations": [
{
"type": "aws-sam",
"request": "direct-invoke",
"name": "lambdas:index.handler (nodejs14.x)",
"invokeTarget": {
"target": "code",
"projectRoot": "${workspace}/lambdas",
"lambdaHandler": "index.handler"
},
"lambda": {
"runtime": "nodejs14.x",
"payload": {"json": {
"Records": [
{
"messageId": "19dd0b57-b21e-4ac1-bd88-01bbb068cb78",
"receiptHandle": "MessageReceiptHandle",
"body": "Hello from SQS!",
"attributes": {
"ApproximateReceiveCount": "1",
"SentTimestamp": "1523232000000",
"SenderId": "123456789012",
"ApproximateFirstReceiveTimestamp": "1523232000001"
},
"messageAttributes": {},
"md5OfBody": "{{{md5_of_body}}}",
"eventSource": "aws:sqs",
"eventSourceARN": "arn:aws:sqs:us-east-1:123456789012:MyQueue",
"awsRegion": "us-east-1"
}
]
}},
"environmentVariables": {
}
}
}
]
}
```

If I try and run the `sam local invoke...` manually I get an error when trying to build the docker image. I have a private docker registry that I'm required to use. Maybe I need to change the registry that sam cli is using?

Also, when I try to use the debug configuration it shows a successful build but then pops up with this window:

Start with the aws-sam direct-invoke launch configuration and reproduce the failure with sam local invoke. Trace how the Docker image is built and selected for the nodejs14.x Lambda when a private registry is required. Done means the required registry is used and the VS Code debug session starts successfully.

Written by the indexing model from the issue text.