With today's update, API Gateway consistently fails to find any of its' defined paths.

For example, the following `serverless.yml` :
```yaml
service: "localtest"

provider:
  name: "aws"
  runtime: "nodejs10.x"

functions:
  hello:
    handler: "handler.hello"
    events:
      - http:
          path: "/"
          method: "get"
          integration: "lambda-proxy"
      - http:
          path: "/test"
          method: "get"
          integration: "lambda-proxy"
plugins:
  - "serverless-localstack"

custom:
  localstack:
    stages:
      - "local"
```

If deployed, will result in the following:
```
~$ sls deploy --stage local
Serverless: Using serverless-localstack
Serverless: Packaging service...
Serverless: Excluding development dependencies...
Serverless: Creating Stack...
Serverless: Checking Stack create progress...
.
Serverless: Stack create finished...
Serverless: Uploading CloudFormation file to S3...
Serverless: Uploading artifacts...
Serverless: Uploading service localtest.zip file to S3 (3.02 KB)...
Serverless: Validating template...
Serverless: Skipping template validation: Unsupported in Localstack
Serverless: Updating Stack...
Serverless: Checking Stack update progress...
.
Serverless: Stack update finished...
Service Information
service: localtest
stage: local
region: us-east-1
stack: localtest-local
resources: 11
api keys:
  None
endpoints:
  GET - http://localhost:4567/restapis/sz3ijrff91/local/_user_request_/
  GET - http://localhost:4567/restapis/sz3ijrff91/local/_user_request_/test
functions:
  hello: localtest-local-hello
layers:
  None
Serverless: Run the "serverless" command to setup monitoring, troubleshooting and testing.
~$ curl http://localhost:4567/restapis/sz3ijrff91/local/_user_request_/
{"message": "Unable to find integration for path /restapis/sz3ijrff91/local/_user_request_/"}
~$ curl http://localhost:4567/restapis/sz3ijrff91/local/_user_request_/test
{"message": "Unable to find integration for path /restapis/sz3ijrff91/local/_user_request_/test"}
```
""" Convert a CloudFormation ACL string (e.g., 'PublicRead') to an S3 ACL string (e.g., 'public-read') """
    return re.sub('(?<!^)(?=[A-Z])', '-', acl).lower()
def retrieve_topic_arn(topic_name):
    topics = aws_stack.connect_to_service('sns').list_topics()['Topics']
    topic_arns = [t['TopicArn'] for t in topics if t['TopicArn'].endswith(':%s' % topic_name)]
    return topic_arns[0]
def get_role_arn(role_arn, **kwargs):
    role_arn = resolve_refs_recursively(kwargs.get('stack_name'), role_arn, kwargs.get('resources'))
    return aws_stack.role_arn(role_arn)
def parse_template(template):
    try:
        return json.loads(template)
    except Exception:
        yaml.add_multi_constructor('', moto.cloudformation.utils.yaml_tag_constructor)
        try:
            return yaml.safe_load(template)
        except Exception:
            return yaml.load(template, Loader=yaml.Loader)
def template_to_json(template):
    template = parse_template(template)
    return json.dumps(template)
def get_resource_type(resource):
    res_type = resource.get('ResourceType') or resource.get('Type') or ''
    parts = res_type.split('::', 1)
    if len(parts) == 1:
        return None
    return parts[1]
def get_service_name(resource):