Adjust sick notes page to show staff statistics

* Instead of showing sick notes in a list,
  the sick notes page shows now an overview
  of the persons and the numbers of days of
  their sick notes for a certain period.

* refs #17658
Add create sick note button to overview page

* On overview page there is now a button for
  office to create a new sick note.
  After redirection to sick note form the
  formerly selected person is set as selected
  in person dropdown.

* refs #17658
Make table rows in sick notes and app list selectable

* As well as the links in table rows as the table rows
  itselves are selectable in applications for leave lists
  and in sick notes list. This increases usability in
  mobile view.

* refs #17658
Adjust layout for sick notes statistics page

* refs #17658
Adjust positioning of error text in sick note convert form

* refs #17658
Remove italic style from vacations not of type holiday

* Color as marker is enough, no need to have
  other text style too.

* refs #17658