Refactor REST API token authentication code to allow for use of existing role-based authorization code.

[aaronweeden]

Description

This refactors the authenticateToken() method in classes/Rest/Controllers/BaseControllerProvider.php so that it sets _USER property of the $request object rather than returning the $user object. This allows for the authorize($request, $requirements) method to be subsequently called.

Motivation and Context

Tests performed

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