Components: withAPIData: Don't restrict endpoints to /wp/v2

[donnapep]

Description

Fixes #3209.

How Has This Been Tested?

1. Set up a site with the appropriate branches of Sensei and Sensei Courses according to the instructions in the parent issue. Set up a post/page in Gutenberg according to the instructions and use the Network inspector.
2. Make sure that a successful request to /sensei/v1/courses is found alongside the request to /wp/v2/course-category.
3. Make sure core blocks aren't affected by this (e.g. Latest Posts), nor other consumers of withAPIData within the framework (e.g. sidebar controls).

Checklist:

• My code is tested.
• My code follows the WordPress code style.
• My code follows has proper inline documentation.