Http-Date Trait Value Validation Bug Fix

[lewisjkl]

Found an issue where if the http-date timestamp format was used in a trait, then the validation would always fail (because it was checked twice, each time with a different format).

e.g. the following would fail:

@trait
structure myTrait {
  @timestampFormat("http-date")
  httpDate: Timestamp
}

@myTrait({ httpDate: "Sun, 06 Nov 1994 08:49:37 GMT"  }) // Invalid string value, `Sun, 06 Nov 1994 08:49:37 GMT`, provided for timestamp, `smithy.api#Timestamp`. Expected an RFC 3339 formatted timestamp (e.g., "1985-04-12T23:20:50.52Z")
string Whatever

A workaround at the moment is to do:

@timestampFormat("http-date")
timestamp HttpDate

@trait
structure myTrait {
  httpDate: HttpDate
}

@myTrait({ httpDate: "Sun, 06 Nov 1994 08:49:37 GMT"  }) // no error
string Whatever

This PR contains a test that reproduces the issue and one way of fixing it (no problem if you all want to do it differently or suggest a different way to me).

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By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

YES

[mtdowling]

Thanks for the PR and proposed fix! I decided to fix this differently that doesn't need the creation of synthetic shapes: #1948

[lewisjkl]

Thanks for the PR and proposed fix! I decided to fix this differently that doesn't need the creation of synthetic shapes: #1948

Great, thank you for such a quick turn around!