Ultimate Member - User Reviews 2.2.6

* Fixed: PHP warnings
* Fixed: Removed `extract()` function to increase security
* Tweak: Changed input_filter to WordPress native sanitize
* Tweak: Template overwrite versioning
* Tweak: User dropdown field added

* Added: Sanitizing fields of the review
* Fixed: "None reviews" text
* Fixed: Extension settings structure

* Fixed: Reply content formatting
* Tweak: jQuery v3 compatibility
* Tweak: WP5.8 widgets screen compatibility