After selecting Knowledge Model when creating questionnaire, a list of available tags is presented to users (client has to make a new request for tags after the selection)
They can choose which tags they want to use in the questionnaire
A new questionnaire is created with only the questions marked with the selected tags
API for selecting tags (will be used for other things in the future)
Update POST /questionnaires to accept tagUuids (a list of tag uuids that should be used, if nothing selected, empty list).