Rename `get-nr-days-in-timetable-day` to `timetable-day-get-nr-rows`
Rename `get-nr-days-in-timetable-day` to `timetable-day-get-nr-rows`

Signed-off-by: Pang Yan Han <22594c345857f664c61cd411f607c4d40a9d4af9@gmail.com>

yanhan/cljs-nusmods,yanhan/cljs-nusmods,yanhan/cljs-nusmods