add code freeze dates (#367)

Author: ddbenson

pkg/controller/releasemanager/schedule/schedule.go

@@ -66,7 +66,9 @@ func init() {
 		date(2021, time.December, 26), // Sun, Holiday break
 		date(2021, time.December, 31), // Holiday break
 
-		date(2022, time.December, 17), // Code freeze
+		date(2022, time.December, 15), // Code freeze
+		date(2022, time.December, 16),
+		date(2022, time.December, 17),
 		date(2022, time.December, 18),
 		date(2022, time.December, 19), // Holiday break
 		date(2022, time.December, 20),