feat: Option to show calendar week in ion-datetime component

[tho-masn]

Feature Request

Ionic version:

[ ] 4.x [ ] 5.x [x] 6.x

Describe the Feature Request It would be useful to have the option to show the calendar weeks in the ion-datetime component. Not sure how it is in the US, but in Europe it's quiet common for specific industries to work with calendar weeks.

Similar to this:

Describe Preferred Solution It probably would make sense to just turn the calendar weeks on via a property like <ion-datetime calendar-weeks="true" />

Describe Alternatives Any solution, which renders the calendar week into the ion-datetime component would be cool.