package:googleapis_auth v2.2.0

• Added quotaProject support to existing credentials classes
  (ServiceAccountCredentials, ClientViaServiceAccount, ClientFromFlow).
• clientViaApplicationDefaultCredentials now extracts quotaProject correctly
  from service account credentials JSON.
• clientViaServiceAccountImpersonation and ImpersonatedAuthClient now accept
  an optional baseClient.
• Application Default Credentials (ADC) now supports impersonated_service_account
  source files.
• Application Default Credentials (ADC) now supports external_account source files
  for Workload Identity Federation using Google Security Token Service.
• Application Default Credentials (ADC) now propagate quota_project_id for
  Service Account credentials.
• Added CredentialsFileException and AuthorizationCallbackException classes.
• Replaced generic exception and error throws (such as Exception, ArgumentError,
  and UnsupportedError) with more specific exception types throughout the package to
  improve error handling and debuggability.
• AuthClientSigningExtension.sign() now accepts an optional serviceAccountEmail
  parameter that is passed down to signBlob.