Used Distributable PostTypes for Check Post Type Permissions via REST API

[mehul0810]

Description of the Change

After checking on how to test and verifying the list of post types received for get_post_types() and distributable_post_types() and then did the necessary change to replace functions.

Closes #912

How to test the Change

Access REST API endpoint: /wp-json/wp/v2/distributor/post-types-permissions (Make sure you use block theme like 2024)

Changelog Entry

Fixed - Bug fix

Credits

Props @peterwilsoncc @mehul0810

Checklist:

• [x] I agree to follow this project's Code of Conduct.
• [ ] I have updated the documentation accordingly.
• [ ] I have added tests to cover my change.
• [ ] All new and existing tests pass.