chore: [IOCOM-1883] Test for push notification permissions utils

[Vangaorth]

Short description

This PR refactors the utility functions used to check and request push notification permissions and adds tests for them.

List of changes proposed in this pull request

• checkPermissions and requestPermissions refactored to improve both readability and testability
• added tests for all the functions in the pushNotifications/utils/index.ts file

How to test

Check that CI tests do succeed.