* make "role" input optional
Per Vault documentation it doesn't have to be provided,
and the auth provider's "default_role" parameter is required
precisely for this case.
https://www.vaultproject.io/api/auth/jwt
* feat: add generic auth
Adds the ability to authenticate against any normal Vault endpoint by added the `authPayload` input.
When an unrecognized method is provided, the action will attempt to hit `v1/auth/<method>/login` with the provided `authPayload and parse out the token in the response
