AWS supports the following Ruby runtimes:

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Name | Identifier | SDK for Ruby | Operating system
-- | -- | -- | --
Ruby 2.7 | ruby2.7 | 3.0.1 | Amazon Linux 2
Ruby 2.5 | ruby2.5 | 3.0.1 | Amazon Linux

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Currently, `localstack/lambda` only contains the `ruby2.5` tag. Will the 2.7 runtime be supported in the (near) future?
records = []
        _run_forward_to_fallback_url(local_url)
        items_after = len(records)
        for record in records:
            self.assertIn('non-existing-lambda', record['headers']['lambda-function-name'])
        self.assertEqual(items_after, 3)
        
        lambda_name = 'test-%s' % short_uid()
        testutil.create_lambda_function(
            handler_file=TEST_LAMBDA_PYTHON, func_name=lambda_name, libs=TEST_LAMBDA_LIBS)
        
        records = []
        inv_results = _run_forward_to_fallback_url(local_url, lambda_name=lambda_name, fallback=False)
        items_after = len(records)
        for record in records:
            headers = record['headers']
            self.assertIn('/lambda/', headers['Authorization'])
            self.assertEqual(record['method'], 'POST')
            self.assertIn('/functions/%s/invocations' % lambda_name, record['path'])
            self.assertTrue(headers.get('X-Amz-Client-Context'))
            self.assertEqual(headers.get('X-Amz-Invocation-Type'), 'RequestResponse')
            self.assertEqual(json.loads(to_str(record['data'])), {'foo': 'bar'})
        self.assertEqual(items_after, 3)
        
        response_payload = inv_results[0]['Payload'].read()
        self.assertEqual(json.loads(response_payload), lambda_result)
        
        lambda_client = aws_stack.connect_to_service('lambda')
        lambda_client.delete_function(FunctionName=lambda_name)