[typescript] Default auth method support and optional param object when all params optional

Created by: davidgamero

Add an optional default?: SecurityAuthentication field to the AuthMethodsConfiguration type that populates a similarly typed optional field on the AuthMethods type. This enables passing a custom object satisfying the SecurityAuthentication interface for authentication purposes in the config either when a client is created or overriding at api call time via config param.

Also carry over optional singleParameter when all params optional from here

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