ISBAT Post Carousel block options - extending Feed settings

[mvlaisavljevic]

Is your feature request related to a problem? Please describe.

No, this would be just an additional option under the Feed settings for the Post Carousel block.

Describe the solution you'd like

An option for users to filter only posts that are under multiple categories.

Additional context/screenshots

Feature request initially submitted on WordPress.org: https://wordpress.org/support/topic/coblock-post-carousel-by-category-and-or/