docs: fix link to example integration test in Contributing.md (aws#15729

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Closes awsgh-15728.


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CONTRIBUTING.md

@@ -251,7 +251,7 @@ The steps here are usually AWS CLI commands but they need not be.
 
 Examples:
 * [integ.destinations.ts](https://github.com/aws/aws-cdk/blob/master/packages/%40aws-cdk/aws-lambda-destinations/test/integ.destinations.ts#L7)
-* [integ.token-authorizer.ts](https://github.com/aws/aws-cdk/blob/master/packages/%40aws-cdk/aws-apigateway/test/authorizers/integ.token-authorizer.ts#L6)
+* [integ.token-authorizer.lit.ts](https://github.com/aws/aws-cdk/blob/master/packages/%40aws-cdk/aws-apigateway/test/authorizers/integ.token-authorizer.lit.ts#L7-L12)
 
 #### yarn watch (Optional)