add oauth_auto_login setting to defaults file

Making the setting configurable thru environment variable

conf/defaults.ini

@@ -246,6 +246,10 @@ disable_signout_menu = false
 # URL to redirect the user to after sign out
 signout_redirect_url =
 
+# Set to true to attempt login with OAuth automatically, skipping the login screen.
+# This setting is ignored if multiple OAuth providers are configured.
+oauth_auto_login = false
+
 #################################### Anonymous Auth ######################
 [auth.anonymous]
 # enable anonymous access

conf/sample.ini

@@ -226,6 +226,10 @@ log_queries =
 # URL to redirect the user to after sign out
 ;signout_redirect_url =
 
+# Set to true to attempt login with OAuth automatically, skipping the login screen.
+# This setting is ignored if multiple OAuth providers are configured.
+;oauth_auto_login = false
+
 #################################### Anonymous Auth ##########################
 [auth.anonymous]
 # enable anonymous access