Add FailureReasons (#35425)

src/Security/Authorization/Core/src/AuthorizationFailure.cs

...rity/Authorization/Core/src/AuthorizationFailureReason.cs

...ity/Authorization/Core/src/AuthorizationHandlerContext.cs

...y/Authorization/Core/src/DefaultAuthorizationEvaluator.cs

src/Security/Authorization/Core/src/PublicAPI.Unshipped.txt

...ty/Authorization/test/DefaultAuthorizationServiceTests.cs

...zation/test/DenyAnonymousAuthorizationRequirementTests.cs

...y/Authorization/test/NameAuthorizationRequirementTests.cs

...horization/test/OperationAuthorizationRequirementTests.cs

.../Authorization/test/RolesAuthorizationRequirementTests.cs

...ion/Handlers/SampleWithFailureReasonRequirementHandler.cs

...Authorization/Requirements/SampleFailReasonRequirement.cs

...thorization/SampleAuthorizationMiddlewareResultHandler.cs

...izationFailureResponse/Authorization/SamplePolicyNames.cs

...horizationFailureResponse/Controllers/SampleController.cs

...ity/samples/CustomAuthorizationFailureResponse/Startup.cs