_onmouseover(e) {
      const target = e.target;
      const hoveredItem = target.closest(".ui5-dp-item");
      if (hoveredItem && this.selectionMode === _CalendarSelectionMode.default.Range && this.selectedDates.length === 1) {
        this._secondTimestamp = this._getTimestampFromDom(hoveredItem);
      }
    }
Set the hovered day as the "_secondTimestamp".
@param { MouseEvent } e
@private