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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 -->

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```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

```

- name: VAULT_TOKEN
    url:
      description: URL to vault service.
      env:
        - name: VAULT_ADDR
      default: 'http://127.0.0.1:8200'
    username:
      description: Authentication user name.
    password:
      description: Authentication password.
    role_id:
      description: Role id for a vault AppRole auth.
      env:
        - name: VAULT_ROLE_ID
    secret_id:
      description: Secret id for a vault AppRole auth.
      env:
        - name: VAULT_SECRET_ID
    auth_method:
      description:
      - Authentication method to be used.
      - C(userpass) is added in version 2.8.
      env:
        - name: VAULT_AUTH_METHOD
      choices:
        - userpass
        - ldap
        - approle
    mount_point:
      description: vault mount point, only required if you have a custom mount point.