Audit trail. Hide the JWT join token (#648)

The JWT join token is a sensible value: we must obfuscate it before writing the
audit trail.

core/api-server/configuration/configuration.go

@@ -93,6 +93,6 @@ func Init() {
 	if os.Getenv("SENSITIVE_LIST") != "" {
 		Config.SensitiveList = strings.Split(os.Getenv("SENSITIVE_LIST"), ",")
 	} else {
-		Config.SensitiveList = []string{"password", "secret", "token"}
+		Config.SensitiveList = []string{"password", "secret", "token", "jwt"}
 	}
 }