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##### SUMMARY
There should be multiline in the cloud-init field, but instead either the module or API itself breaks it and sends the whole text as a string in double quotes.

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
scaleway_user_data

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
ansible 2.8.3
```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```paste below

```

##### OS / ENVIRONMENT
<!--- Provide all relevant information below, e.g. target OS versions, network device firmware, etc. -->


##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->

```yaml
  - scaleway_user_data:
      server_id: "{{ scaleway_compute.msg.id }}"
      region: "{{ region }}"
      user_data:
        cloud-init: |
          #cloud-config
          # final_message
          # default: cloud-init boot finished at $TIMESTAMP. Up $UPTIME seconds
          # this message is written by cloud-final when the system is finished
          # its first boot
          final_message: "The system is finally up, after $UPTIME seconds"
```

1. Update the cloud-init and start the server
2. Cloud-init throws an error
`2019-11-18 19:27:31,692 - __init__.py[WARNING]: Unhandled non-multipart (text/x-not-multipart) userdata: 'b'"#cloud-config\\\\nfinal_me'...'`

<!--- Paste example playbooks or commands between quotes below -->

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##### EXPECTED RESULTS
<!--- Describe what you expected to happen when running the steps above -->
```
root@test-cloudinit:~# curl --local-port 1-1023 http://169.254.42.42/user_data/cloud-init/ -w "\n"
#cloud-config
# final_message
# default: cloud-init boot finished at $TIMESTAMP. Up $UPTIME seconds
# this message is written by cloud-final when the system is finished
# its first boot
final_message: "The system is finally up, after $UPTIME seconds"
```

##### ACTUAL RESULTS
<!--- Describe what actually happened. If possible run with extra verbosity (-vvvv) -->

<!--- Paste verbatim command output between quotes -->
```
root@test-cloudinit:~# curl --local-port 1-1023 http://169.254.42.42/user_data/cloud-init/ -w "\n"
"#cloud-config\n# final_message\n# default: cloud-init boot finished at $TIMESTAMP. Up $UPTIME seconds\n# this message is written by cloud-final when the system is finished\n# its first boot\nfinal_message: \"The system is finally up, after $UPTIME seconds\"\n"
```

d = self.module.params.get('query_parameters')
        if params is not None:
            d.update(params)
        query_string = urlencode(d, doseq=True)
        if path[0] == '/':
            path = path[1:]
        return '%s/%s?%s' % (self.module.params.get('api_url'), path, query_string)
    def send(self, method, path, data=None, headers=None, params=None):
        url = self._url_builder(path=path, params=params)
        self.warn(url)
        data = self.module.jsonify(data)
        if headers is not None:
            self.headers.update(headers)
        resp, info = fetch_url(
            self.module, url, data=data, headers=self.headers, method=method,
            timeout=self.module.params.get('api_timeout')
        )
        
        if info['status'] == -1:
            self.module.fail_json(msg=info['msg'])
        return Response(resp, info)
    @staticmethod
    def get_user_agent_string(module):
        return "ansible %s Python %s" % (module.ansible_version, sys.version.split(' ')[0])
    def get(self, path, data=None, headers=None, params=None):