Add required pydantic version in setup

[kt474]

Summary

Related to #1577 - users that already have pydantic installed in the their environments may run into incompatibility issues because the version of pydantic required is not specified in setup.py.

Details and comments

Fixes #

[SamFerracin]

👍

[coveralls]

Pull Request Test Coverage Report for Build 9584623842

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This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 82.0%

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Totals
Change from base Build 9584358599:	0.0%
Covered Lines:	6077
Relevant Lines:	7411

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💛 - Coveralls