gddo-server: log configuration settings as Debug only

To prevent leaking sensitive data in the normal case, use the Debug
logging level instead of Info when logging credentials.

There are very sensitive pieces of data in the settings, namely GitHub
secrets, Redis database passwords, etc. In the normal case, these are
logged. To prevent accidental leaking of credentials, only print
settings map when logging in Debug mode.

Change-Id: I4144074bf2b26a940fd9bfb4ed695b9112e67521
GitHub-Last-Rev: 70b36f748181c76ec74a3629d4375a64e2d5a128
GitHub-Pull-Request: golang/gddo#545
Reviewed-on: https://go-review.googlesource.com/102278
Reviewed-by: Parker Moore <parkrmoore@gmail.com>
Reviewed-by: Tuo Shan <shantuo@google.com>
diff --git a/gddo-server/config.go b/gddo-server/config.go
index 07845a2..199f262 100644
--- a/gddo-server/config.go
+++ b/gddo-server/config.go
@@ -117,7 +117,7 @@
 	// Set defaults based on other configs
 	setDefaults(v)
 
-	log.Info(ctx, "config values loaded", "values", v.AllSettings())
+	log.Debug(ctx, "config values loaded", "values", v.AllSettings())
 	return v, nil
 }