When PUTting an S3 object to Localstack with attached Metadata, if a key contains an underscore it is replaced with a dash.

However, when the same request is performed against the real S3, the key is not modified.

Example Input:
key_with_underscores => test

Localstack Result:
key-with-underscores => test

S3 Result:
key_with_underscores => test

Localstack Version: 0.10.5

Tested using AWS v2 S3 client
sqs_client = aws_stack.connect_to_service('sqs')
        try:
            queue_url = queue_url_for_arn(notif['Queue'])
            sqs_client.send_message(QueueUrl=queue_url, MessageBody=message)
        except Exception as e:
            LOGGER.warning('Unable to send notification for S3 bucket "%s" to SQS queue "%s": %s' %
                (bucket_name, notif['Queue'], e))
    if notif.get('Topic'):
        sns_client = aws_stack.connect_to_service('sns')
        try:
            sns_client.publish(TopicArn=notif['Topic'], Message=message, Subject='Amazon S3 Notification')
        except Exception:
            LOGGER.warning('Unable to send notification for S3 bucket "%s" to SNS topic "%s".' %
                (bucket_name, notif['Topic']))
    
    lambda_function_config = notif.get('CloudFunction') or notif.get('LambdaFunction')
    if lambda_function_config:
        
        connection_config = botocore.config.Config(read_timeout=300)
        lambda_client = aws_stack.connect_to_service('lambda', config=connection_config)
        try:
            lambda_client.invoke(FunctionName=lambda_function_config,
                                 InvocationType='Event', Payload=message)
        except Exception:
            LOGGER.warning('Unable to send notification for S3 bucket "%s" to Lambda function "%s".' %
                (bucket_name, lambda_function_config))
    if not filter(lambda x: notif.get(x), NOTIFICATION_DESTINATION_TYPES):
        LOGGER.warning('Neither of %s defined for S3 notification.' %
            '/'.join(NOTIFICATION_DESTINATION_TYPES))
def get_cors(bucket_name):