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##### SUMMARY
When you wan't to create / update a repo which needs tls client auth for sync (like redhat repos)
this breaks because this module uses the following vars:
```python
ca_cert
client_cert
client_key
```
which overlap with the fetch_url vars which also use those.
So the api calls to your local pulp server are also made with tls client auth and
not only for the remote repo.


This only affects users who wan't to sync RedHat repos which needs TLS client auth.


The bug happens only in call **server.set_repo_list()** of the module:
```python
    server = pulp_server(module, pulp_host, repo_type, wait_for_completion=wait_for_completion)
    server.set_repo_list()
    repo_exists = server.check_repo_exists(repo)

```

the call to **fetch_url** has overlapping vars the module defines:
```python
   def set_repo_list(self):
        url = "%s/pulp/api/v2/repositories/?details=true" % self.host
        response, info = fetch_url(self.module, url, method='GET')

        if info['status'] != 200:
            print(response)
            print(info)
            self.module.fail_json(
                msg="Request failed",
                status_code=info['status'],
                response=info['msg'],
                url=url)

        self.repo_list = json.load(response)
```


##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
pulp_repo

##### ANSIBLE VERSION

```
ansible 2.8.2
```

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

<!--- Paste example playbooks or commands between quotes below -->
```yaml
   pulp_repo:
      # connect / auth options
      pulp_host: REDACTED
      url_username: admin
      url_password: "{{ pulp_admin_password }}"
      force_basic_auth: true
      # actual repo options
      name: "SOME REPO NAME"
      relative_url: "/redhat/7/example"
      ca_cert: "/etc/rhsm/ca/redhat-uep.pem"
      client_cert: "/etc/pki/entitlement/999999999999999999.pem "
      client_key: "/etc/pki/entitlement/9999999999999999999-key.pem"
      feed: "https://cdn.redhat.com/content/dist/rhel/server/7/7Server/x86_64/os/"
      wait_for_completion: yes
```

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

##### EXPECTED RESULTS
create / modify of the pulp repo on the server


##### ACTUAL RESULTS
Connection failure: [SSL: SSL_HANDSHAKE_FAILURE] ssl handshake failure (_ssl.c:1822)

<!--- Paste verbatim command output between quotes -->
```paste below

```

- CA certificate string used to validate the feed source SSL certificate.
        This can be the file content or the path to the file.
    type: str
    aliases: [ importer_ssl_ca_cert ]
  client_cert:
    description:
      - Certificate used as the client certificate when synchronizing the
        repository. This is used to communicate authentication information to
        the feed source. The value to this option must be the full path to the
        certificate. The specified file may be the certificate itself or a
        single file containing both the certificate and private key. This can be
        the file content or the path to the file.
    type: str
    aliases: [ importer_ssl_client_cert ]
  client_key:
    description:
      - Private key to the certificate specified in I(importer_ssl_client_cert),
        assuming it is not included in the certificate file itself. This can be
        the file content or the path to the file.
    type: str
    aliases: [ importer_ssl_client_key ]
  name:
    description:
      - Name of the repo to add or remove. This correlates to repo-id in Pulp.
    required: true
  proxy_host:
    description:
      - Proxy url setting for the pulp repository importer. This is in the
        format scheme://host.
    required: false