feat(auth): allow providing raw private key and email instead of filepath

[mharrisb1]

Overview

Closes #87: Allow the user to provide access key via parameter

Allows user to use either filepath or raw email and secret values for key_file provider.

CREATE SECRET (
    TYPE gsheet,
    PROVIDER key_file,
    FILEPATH '<path_to_JSON_file_with_private_key>'
);

-- or
CREATE SECRET (
    TYPE gsheet,
    PROVIDER key_file,
    EMAIL '<service_account_email>',
    SECRET '<private_key>'
);

[archiewood]

This seems like a good idea to add.

Some suggestions inline