Resolves spotless issue

Author: alecharp

core/src/main/java/hudson/Util.java

@@ -94,13 +94,11 @@
 import java.util.EnumSet;
 import java.util.HexFormat;
 import java.util.List;
-import java.util.Locale;
 import java.util.Map;
 import java.util.MissingResourceException;
 import java.util.Properties;
 import java.util.ResourceBundle;
 import java.util.Set;
-import java.util.SimpleTimeZone;
 import java.util.StringTokenizer;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicBoolean;