fix(datepicker): hour decrement loops incorrectly when minDate hour i…

[nenaki]

Description

Fixes incorrect behaviour in the constrainTime method where clicking
the hour decrement button causes the hour to loop incorrectly
(e.g. 9 → 11 → 10 → 9) when a minDate with a specific hour is set.

Root Cause

A switch(true) case in constrainTime was incorrectly setting
returnTimeTriple[0] = 11 and flipping this.pm = true whenever
the decremented hour was exactly one below the minDate hour.
This case was redundant as AM/PM toggling is already handled
by toggleAMPMIfNotMinDate before constrainTime is called.

Fix

Removed the redundant and incorrect case from the switch(true)
block in constrainTime.

Fixes #19557