Provide Vault App role method to the lookup.
https://www.vaultproject.io/docs/auth/approle.html
Usage :
`{{ lookup('hashi_vault', 'secret=secret/hello:value auth_method=approle role_id=myroleid secret_id=mysecretid url=http://myvault:8200')}}`
You can skip `role_id` and `secret_id` if you set `VAULT_ROLE_ID` and `VAULT_SECRET_ID` environment variables.