Serverless remove doesn't delete iam role

Bug Report

Description

I deploy a simple API via serverless with a custom log in serverless.yml. When I use 'serverless remove' to remove the API, I find the IAM role is not deleted. Not sure it is designed as expacted.
serverless version 1.6X

1. What did you do?
2. What happened?
   When I run 'serverless remove' successfully, I still can find an IAM role from AWS console 'arn:aws:iam::XXX:role/serverlesstest-hello-dev-us-east-1-apiGatewayLogsRole',
3. What should've happened?
   The IAM role is not deleted.
4. What's the content of your serverless.yml file?

service: serverlesstest-hello

provider:
  name: aws
  runtime: nodejs10.x
  region: us-east-1
  stage: dev
  timeout: 30
  logs:
    restApi:
      format: '{"request_id":"$context.requestId","@env":"$context.stage","@gateway_id":"$context.apiId","method":"$context.httpMethod","path":"$context.resourcePath","api_key_id":"$context.identity.apiKeyId","status":"$context.status","xray_id":"$context.xrayTraceId","full_path":"$context.path","principal_id":"$context.authorizer.principalId","extended_request_id":"$context.extendedRequestId","caller":"$context.identity.caller","source_ip":"$context.identity.sourceIp","user":"$context.identity.user","user_agent":"$context.identity.userAgent","aws_endpoint_request_id":"$context.awsEndpointRequestId","resource_id":"$context.resourceId","request_time":"$context.requestTime","request_time_epoch":"$context.requestTimeEpoch","domain_name":"$context.domainName","authorizer_integration_latency":"$context.authorizer.integrationLatency","integration_latency":"$context.integrationLatency","integration_status":"$context.integrationStatus","response_latency":"$context.responseLatency","response_length":"$context.responseLength","error_message":"$context.error.message","error_response_type":"$context.error.responseType","error_validation_error":"$context.error.validationErrorString"}'
      level: INFO

functions:
  helloWorld:
    handler: handler.helloWorld
    events:
      - http:
          path: hello-world
          method: get
          cors: true

1. What's the output you get when you use the SLS_DEBUG=* environment variable (e.g. SLS_DEBUG=* serverless deploy)

Similar or dependent issues:

• #12345