Remove Swift DispatchQueue usage from logins

[lougeniaC64]

As a part of our effort to clean up the DispatchQueue usage in the Swift layer of our components, use the logins component (which is stable and not under active development) to test the removal of the DispatchQueue usage there. This involves removing the instantiation of the DispatchQueue` in LoginsStorage.swift and all the calls to submit work items to the queue within the API functions in that file.

┆Issue is synchronized with this Jira Task ┆epic: Refactor iOS DispatchQueues ┆sprintEndDate: 2022-08-05