0.322.1

This release fixes the built-in UUID, Date, DateTime, and Time scalars
to reject non-string variable values with a standard coercion error instead of
raising an unhandled AttributeError/TypeError inside the parser.

Previously a value like {"id": 469610.0} sent into a UUID position crashed
with 'float' object has no attribute 'replace' and surfaced in error
trackers as a server-side exception. The Decimal scalar keeps accepting
numeric input by stringifying it, as before.

This release was contributed by @simonline in #4525