Fix #3192: Calendar monthpicker fix for disabled dates

[melloware]

Defect Fixes

Fix #3192: Calendar monthpicker fix for disabled dates

Scenario:

let minDate = new Date(2022, 7, 2);
let maxDate = new Date(2022, 7, 31);

The issue was testing against the 1st of the month !isSelectable(1, i, currentYear) . this means that it would disable this month in the scenario above. In fact there is no good "day" to use other than 0 and then test for day > 0.