Custom scopes support in U2M authentication

[Tejas-Kochar]

Summary

• Introduce factory pattern for testability of PersistentAuth.
• Pass scopes and disableOfflineAccess in U2M authentication instead of hard coded "all-apis".
• only add "offline-access" if disableOfflineAccess is not set.

Testing

• unit tests for different configurations of disableOfflineAccess in persistent_auth_test.go.
• integration test (with mocking) to ensure configured scopes used for authentication inauth_u2m_test.go.

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NO_CHANGELOG=true

[github-actions]

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Inputs:

• PR number: 1390
• Commit SHA: fe702d29fda88c9e0e4e3884460263ffab2e6ac3

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