Allow sorting by column (#2691)
* Test orderby in filter
* Add orderby parameter to filter endpoint
* Rename validate_where_parameter
* Validate orderby parameter
* Test validate orderby parameter
* Make where parameter optional
* Test execute_filter_query without where param
* Add e2e test of filter endpoint parameter orderby
* Add e2e test of filter endpoint without where parameter
* Test e2e filter endpoint with orderby parameter
* Add orderby parameter to docs
* Update openapi.json
