# Type of request: This is a ...
[ ] bug report
[x] feature request

# Detailed description
As a Developer,
I want to be able to simulate BadDigest and InvalidDigest errors,
So that I can test the error handling logic

## Expected behavior
https://docs.aws.amazon.com/AmazonS3/latest/API/ErrorResponses.html
BadDigest: The Content-MD5 you specified did not match what we received.
InvalidDigest: The Content-MD5 you specified is not valid.

## Actual behavior
localstack returns InvalidDigest when MD5 does not match payload.


self._assert_contained({'Content-Type': 'application/json'}, response[2])
    @mock.patch('localstack.services.awslambda.lambda_api.run_lambda')
    def test_invoke_integer_json_response(self, mock_run_lambda):
        with self.app.test_request_context() as context:
            self._request_response(context)
            mock_run_lambda.return_value = '1234'
            response = lambda_api.invoke_function(self.FUNCTION_NAME)
            self.assertEqual(b'1234\n', response[0].response[0])
            self.assertEqual(200, response[1])
            self._assert_contained({'Content-Type': 'application/json'}, response[2])
    @mock.patch('localstack.services.awslambda.lambda_api.run_lambda')
    def test_invoke_float_json_response(self, mock_run_lambda):
        with self.app.test_request_context() as context:
            self._request_response(context)
            mock_run_lambda.return_value = '1.3'
            response = lambda_api.invoke_function(self.FUNCTION_NAME)
            self.assertEqual(b'1.3\n', response[0].response[0])
            self.assertEqual(200, response[1])
            self._assert_contained({'Content-Type': 'application/json'}, response[2])
    @mock.patch('localstack.services.awslambda.lambda_api.run_lambda')
    def test_invoke_boolean_json_response(self, mock_run_lambda):
        with self.app.test_request_context() as context:
            self._request_response(context)
            mock_run_lambda.return_value = 'true'
            response = lambda_api.invoke_function(self.FUNCTION_NAME)
            self.assertEqual(b'true\n', response[0].response[0])
            self.assertEqual(200, response[1])
            self._assert_contained({'Content-Type': 'application/json'}, response[2])
    @mock.patch('localstack.services.awslambda.lambda_api.run_lambda')
    def test_invoke_null_json_response(self, mock_run_lambda):