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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 -->

<!--- HINT: You can paste gist.github.com links for larger files -->

##### 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"
```

return self.send(method='GET', path=path, data=data, headers=headers, params=params)
    def put(self, path, data=None, headers=None, params=None):
        return self.send(method='PUT', path=path, data=data, headers=headers, params=params)
    def post(self, path, data=None, headers=None, params=None):
        return self.send(method='POST', path=path, data=data, headers=headers, params=params)
    def delete(self, path, data=None, headers=None, params=None):
        return self.send(method='DELETE', path=path, data=data, headers=headers, params=params)
    def patch(self, path, data=None, headers=None, params=None):
        return self.send(method="PATCH", path=path, data=data, headers=headers, params=params)
    def update(self, path, data=None, headers=None, params=None):
        return self.send(method="UPDATE", path=path, data=data, headers=headers, params=params)
    def warn(self, x):
        self.module.warn(str(x))
SCALEWAY_LOCATION = {
    'par1': {'name': 'Paris 1', 'country': 'FR', "api_endpoint": 'https://api.scaleway.com/instance/v1/zones/fr-par-1'},
    'EMEA-FR-PAR1': {'name': 'Paris 1', 'country': 'FR', "api_endpoint": 'https://api.scaleway.com/instance/v1/zones/fr-par-1'},
    'ams1': {'name': 'Amsterdam 1', 'country': 'NL', "api_endpoint": 'https://api.scaleway.com/instance/v1/zones/nl-ams-1'},
    'EMEA-NL-EVS': {'name': 'Amsterdam 1', 'country': 'NL', "api_endpoint": 'https://api.scaleway.com/instance/v1/zones/nl-ams-1'}
}
SCALEWAY_ENDPOINT = "https://api.scaleway.com"
SCALEWAY_REGIONS = [
    "fr-par",
    "nl-ams",
]
SCALEWAY_ZONES = [
    "fr-par-1",
    "nl-ams-1",
]