We're using an old version of `boto` (through `moto`) to detect the available regions for Lambda (and other APIs). We should switch from `boto` to the newer `boto3` library, which includes the up-to-date endpoints.

```
code/localstack/localstack/services/cloudformation/cloudformation_starter.py", line 502, in Lambda_create_from_cloudformation_json
    return Lambda_create_from_cloudformation_json_orig(resource_name, cloudformation_json, region_name)
  File "/opt/code/localstack/.venv/lib/python3.7/site-packages/moto/awslambda/models.py", line 519, in create_from_cloudformation_json
    backend = lambda_backends[region_name]
KeyError: 'eu-west-2'
```
stack_name = self._get_param('StackName')
        stack = self.cloudformation_backend.get_stack(stack_name)
        logical_resource_id = self._get_param('LogicalResourceId')
        if not stack:
            msg = ('Unable to find CloudFormation stack "%s" in region %s' %
                   (stack_name, aws_stack.get_region()))
            if aws_stack.get_region() != self.region:
                msg = '%s/%s' % (msg, self.region)
            LOG.warning(msg)
            response = aws_responses.flask_error_response(msg, code=404, error_type='ResourceNotFoundException')
            return 404, response.headers, response.data
        for stack_resource in stack.stack_resources:
            
            
            if stack_resource and stack_resource.logical_resource_id == logical_resource_id:
                resource = stack_resource
                break
        else:
            raise ValidationError(logical_resource_id)
        template = self.response_template(
            responses.DESCRIBE_STACK_RESOURCE_RESPONSE_TEMPLATE)
        return template.render(stack=stack, resource=resource)
    responses.CloudFormationResponse.describe_stack_resource = describe_stack_resource
    
    def cf_describe_stack_events(self):