Updated py-JWT to 1.4.2.

[v1.4.2][1.4.2]
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### Fixed
- A PEM-formatted key encoded as bytes could cause a `TypeError` to be raised [#213][213]

[v1.4.1][1.4.1]
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### Fixed
- Newer versions of Pytest could not detect warnings properly [#182][182]
- Non-string 'kid' value now raises `InvalidTokenError` [#174][174]
- `jwt.decode(None)` now gracefully fails with `InvalidTokenError` [#183][183]

(wiz)