Add decoding option TimeTagToAny to produce RFC3339 when decoding time into interface{}

[ssuriyan7]

Adds a decoding option to specify how to decode CBOR tag 0 or 1 data item into an empty interface.
Based on the specified mode, Unmarshal can return a time.Time value or a time string in a specific format.

Description

PR Was Proposed and Welcomed in Currently Open Issue

• This PR was proposed and welcomed by maintainer(s) in issue feature: Add TimeTagToAny option to produce RFC3339 when decoding time into interface{} #496
• Closes or Updates Issue feature: Add TimeTagToAny option to produce RFC3339 when decoding time into interface{} #496

Checklist (for code PR only, ignore for docs PR)

• Include unit tests that cover the new code
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[fxamacker]

@ssuriyan7 Thanks for opening this PR! I'll try to take a look this week/weekend. 🙏

[fxamacker]

@ssuriyan7 Thanks for opening this PR! 👍

I left some suggestions to make this deterministic by preserving time zone. This will also simplify tests by eliminating the need to have tests deal with nondeterministic output.

[ssuriyan7]

@fxamacker , Thanks for your suggestion. I've incorporated them. Please take a look.

[fxamacker]

LGTM! Thanks for contributing this PR!