[DateTimeRangePicker] Different selection flow option

[LukasTy]

Created from: #12586 (comment)

The current selection flow for the component is: Start Date -> Start Time -> End Date -> End Time
A user is asking for the following flow: Start Date -> End Date -> Start Time -> End Time

During the development, we were considering both and initially implemented the latter.
For the release, we pivoted towards the first flow.

Both flows could make sense, especially under different circumstances and for different date and time selections.

One option could be to have the flow controllable, keeping the existing as default, but adding the option to change it.

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[LukasTy]

Adding the "waiting for 👍" label to gauge the interest for it.

[cwittlinger89]

Would be greatly appreciated if this comes!