fix(webmasters): update the API

src/apis/webmasters/README.md

@@ -15,10 +15,10 @@ All documentation and usage information can be found on [GitHub](https://github.
 Information on classes can be found in [Googleapis Documentation](https://googleapis.dev/nodejs/googleapis/latest/webmasters/classes/Webmasters.html).
 
 ## License
-This library is licensed under Apache 2.0. Full license text is available in [LICENSE](https://github.com/googleapis/google-api-nodejs-client/blob/master/LICENSE).
+This library is licensed under Apache 2.0. Full license text is available in [LICENSE](https://github.com/googleapis/google-api-nodejs-client/blob/main/LICENSE).
 
 ## Contributing
-We love contributions! Before submitting a Pull Request, it's always good to start with a new issue first. To learn more, see [CONTRIBUTING](https://github.com/google/google-api-nodejs-client/blob/master/.github/CONTRIBUTING.md).
+We love contributions! Before submitting a Pull Request, it's always good to start with a new issue first. To learn more, see [CONTRIBUTING](https://github.com/google/google-api-nodejs-client/blob/main/.github/CONTRIBUTING.md).
 
 ## Questions/problems?
 * Ask your development related questions on [StackOverflow](http://stackoverflow.com/questions/tagged/google-api-nodejs-client).