Add support for RSA4b, b1, c, RSA16 (Authentication)

[AndyNicks]

Add support for the following requirements: RSA4b, b1, c, RSA16

As stated at https://docs.ably.io/client-lib-development-guide/features/#RSA4b https://docs.ably.io/client-lib-development-guide/features/#RSA4c https://docs.ably.io/client-lib-development-guide/features/#RSA16

see details https://github.com/ably/docs/blob/main/content/client-lib-development-guide/versions/features-1-1__1-2.diff

Acceptance Criteria:

Implement the support for the requirements above

Update the spreadsheet

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