Refactor - create `get-set-from-seq-of-maps-with-day-key` function
Refactor - create `get-set-from-seq-of-maps-with-day-key` function

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

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