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##### SUMMARY
<!--- Explain the problem briefly below -->
Hi, i am trying to read a secret from the following path
        secret: "{{ lookup('hashi_vault', 'namespace={{NAMESPACE}} secret={{ BRAND }}/{{ ENVIRONMENT }}/secrets/placeholder:foo url={{ VAULT_ADDR }} auth_method={{ VAULT_AUTH_METHOD }} role_id={{ VAULT_ROLE_ID }} secret_id={{ VAULT_SECRET_ID }}')}}"

but this fails with no secret found at location. 
we are using enterprise and this uses the KV engine

vault kv get {{ BRAND }}/{{ ENVIRONMENT }}/secrets/placeholder:foo


##### ISSUE TYPE
- Bug Report
unable to read from kv data store

##### COMPONENT NAME
<!--- Write the short name of the module, plugin, task or feature below, use your best guess if unsure -->
hashi_vault

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
2.8
```

##### 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 -->

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

```

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##### EXPECTED RESULTS
<!--- Describe what you expected to happen when running the steps above -->


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

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

```

data = self.client.read(self.secret)
        if data is None:
            raise AnsibleError("The secret %s doesn't seem to exist for hashi_vault lookup" % self.secret)
        if self.secret_field == '':
            return data['data']
        if self.secret_field not in data['data']:
            raise AnsibleError("The secret %s does not contain the field '%s'. for hashi_vault lookup" % (self.secret, self.secret_field))
        return data['data'][self.secret_field]
    def check_params(self, **kwargs):
        username = kwargs.get('username')
        if username is None:
            raise AnsibleError("Authentication method %s requires a username" % self.auth_method)
        password = kwargs.get('password')
        if password is None:
            raise AnsibleError("Authentication method %s requires a password" % self.auth_method)
        mount_point = kwargs.get('mount_point')
        return username, password, mount_point
    def auth_userpass(self, **kwargs):