Fix deprecation: 'onChange(of:perform:)' was deprecated in iOS 17.0

[ayushraj05]

There is a deprecation warning in the codebase related to onChange(of:perform:) that persists at one specific location, despite a prior attempt to fix similar warnings.
#762
#773
#774

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Expectation

Replace the deprecated onChange(of:perform:) with the updated version, using either a two-parameter or zero-parameter action closure.

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Location

The warning occurs at the following location:

• ./OBAKit/Onboarding/RegionPicker/RegionPickerView.swift:91:14

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Previous Context

This issue was previously addressed in a past pull request, but it seems like this particular location was missed or there was a conflict.

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Screenshots