Update README.md

Add Code of Conduct link

Author: Doug Mahugh

README.md

@@ -97,3 +97,5 @@ To view or log issues, see [issues](https://github.com/microsoftgraph/msgraph-sd
 ## License
 
 Copyright (c) Microsoft Corporation. All Rights Reserved. Licensed under the MIT [license](LICENSE).
+
+This project has adopted the [Microsoft Open Source Code of Conduct](https://opensource.microsoft.com/codeofconduct/). For more information see the [Code of Conduct FAQ](https://opensource.microsoft.com/codeofconduct/faq/) or contact [opencode@microsoft.com](mailto:opencode@microsoft.com) with any additional questions or comments.