Update dependency google-auth to v1.23.0

Author: renovate-bot

requirements.txt

@@ -4,7 +4,7 @@ cffi==1.14.2
 chardet==3.0.4
 future==0.18.2
 google-api-core==1.22.1
-google-auth==1.21.0
+google-auth==1.23.0
 google-cloud-bigquery==1.27.2
 google-cloud-core==1.4.1
 google-crc32c==1.0.0