[FR] Support client option in create / update tenant

[JoeEnnever]

Is your feature request related to a problem? Please describe.
Currently the library does not support sending the client key in the createTenant/updateTenant methods.

Describe the solution you'd like
Support the client key as described in the documentation linked above.

Describe alternatives you've considered
I'm manually sending the request using fetch, but it bypasses all the validation that the normal methods provide, and is a pain to get the authentication headers.

Additional context
N/A

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