Fix Return For Token Authenticator

[jherdman]

I pinpointed an issue I was experiencing with the Token Authenticator
and it always returning undefined. This seemed to be something to do
with unwrapping Promise values. The makeRequest method was
unnecessarily wrapping fetch. In removing this wrapping and leaning
more on built in Promise semantics the problem went away.

[jherdman]

To clarify, this.session.authenticate(...) still returns undefined, but now I can actually access the session data.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[jpadilla]

@fenichelar thoughts on this, at a glance it LGTM

[fenichelar]

@jherdman Nice clean up!

@jpadilla Agreed.

I'm not sure I understand how this changes anything with regards to accessing the session data and I am able to access it as it currently stands. But this is definitely a good improvement from a simplification standpoint.