remove unused import

Author: vladak

plugins/src/main/java/opengrok/auth/plugin/configuration/Configuration.java

@@ -30,7 +30,6 @@
 import java.io.OutputStream;
 import java.io.Serializable;
 import java.util.ArrayList;
-import java.util.Arrays;
 import java.util.List;
 
 import com.fasterxml.jackson.annotation.JsonAutoDetect;