chore: add link to guide on enable debug logging (#1723)

* chore: add link to guide on enable debug logging

* wording

Co-authored-by: Lawrence Qiu <[email protected]>

---------

Co-authored-by: Lawrence Qiu <[email protected]>

Author: zhumin8

README.md

@@ -36,6 +36,7 @@ information, refer to [documentation](https://cloud.google.com/docs/authenticati
       * [Gradle](#gradle)
       * [Scala](#scala)
   * [Migrating from GoogleCredential to GoogleCredentials](#migrating-from-googlecredential-to-googlecredentials)
+* [Troubleshooting](#troubleshooting)
 * [google-auth-library-oauth2-http](#google-auth-library-oauth2-http)
   * [Application Default Credentials](#application-default-credentials)
   * [ImpersonatedCredentials](#impersonatedcredentials)
@@ -171,6 +172,9 @@ For [Google Api Client Library](https://cloud.google.com/apis/docs/client-librar
 For [Cloud Client Libraries](https://cloud.google.com/apis/docs/client-libraries-explained#cloud-client-libraries), the library will follow ADC to create a 
 default GoogleCredential. Users do not need to manually create any Credentials or pass it into the library.
 
+### Troubleshooting
+This library provides logging for debugging purposes. Please refer to [this guide](https://cloud.google.com/java/docs/bom#client_library_debug_logging) to enable debug logging feature.
+
 ## google-auth-library-oauth2-http
 
 ### Application Default Credentials