Multiple runs of deploy_lambda_function.sh is causing lots of issues

```

An error occurred (ResourceConflictException) when calling the CreateFunction operation: Function already exist: yet-another-chatbot-function

Function ARN:

Waiting for Lambda function to be active...
Waiting for Lambda function to be ready for an update...

Updating Lambda function code...
Update status: "InProgress"
```

Start by reading deploy_lambda_function.sh and reproduce the deployment twice to observe the ResourceConflictException and update status. Trace how repeated runs create or update the Lambda function; done means subsequent runs complete without the reported conflict or remaining stuck in progress.

Written by the indexing model from the issue text.