avoid wildcard imports

Author: Vladimir Kotal

opengrok-web/src/test/java/org/opengrok/web/api/v1/filter/IncomingFilterTest.java

@@ -42,7 +42,11 @@
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertTrue;
-import static org.mockito.Mockito.*;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
 
 public class IncomingFilterTest {
     @Before