Feature/category not in support

[oscarssanchez]

Description of the Change

This PR adds support for category__not_in param and fixes #1947

Alternate Designs

Benefits

Possible Drawbacks

Verification Process

1.- Create a post and add to a test category
2.- Use pre_get_posts or WP_Query to search with category__not_in set to the test category id
3.- Post should be excluded

Checklist:

• I have read the CONTRIBUTING document.
• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my change.
• All new and existing tests passed.

Applicable Issues

Changelog Entry

[oscarssanchez]

Added tag__not_in support @felipeelia can you please take another peek?

[felipeelia]

@oscarssanchez I'm terribly sorry for not seeing this before but can we wrap those (array) $variable statements with an array_values() call? That way we avoid problems if some plugin or theme decides to send an associative array. Again, sorry for the back and forth here.
When you have it done, can you please assign it to @Rahmon to review? Thanks!

[Rahmon]

LGTM 👍

[Rahmon]

@oscarssanchez can you please update the PR to be able to merge?

[oscarssanchez]

Branch updated @Rahmon :)