chore(apiusagemonitoring-filter): add warning (deprecated default cli…

…ent tracking pattern) for library users (#949)

Signed-off-by: Maxim Tschumak <maxim.tschumak@gmail.com>

skipper.go

@@ -507,6 +507,8 @@ type Options struct {
 	ApiUsageMonitoringRealmKeys             string
 	ApiUsageMonitoringClientKeys            string
 	ApiUsageMonitoringRealmsTrackingPattern string
+	// Deprecated: ApiUsageMonitoringDefaultClientTrackingPattern
+	ApiUsageMonitoringDefaultClientTrackingPattern string
 
 	// Default filters directory enables default filters mechanism and sets the directory where the filters are located
 	DefaultFiltersDir string
@@ -761,6 +763,10 @@ func Run(o Options) error {
 		return err
 	}
 
+	if o.ApiUsageMonitoringDefaultClientTrackingPattern != "" {
+		log.Warn(`"ApiUsageMonitoringDefaultClientTrackingPattern" option is deprecated`)
+	}
+
 	// *DEPRECATED* create authentication for Innkeeper
 	inkeeperAuth := innkeeper.CreateInnkeeperAuthentication(innkeeper.AuthOptions{
 		InnkeeperAuthToken:  o.InnkeeperAuthToken,