Fix imports of unit test methods

Author: junichi11

test/unit/src/org/netbeans/modules/php/wordpress/util/UnderscoresUtilsTest.java

@@ -41,7 +41,6 @@
  */
 package org.netbeans.modules.php.wordpress.util;
 
-import static junit.framework.Assert.assertEquals;
 import org.junit.Test;
 import org.netbeans.junit.NbTestCase;
 

test/unit/src/org/netbeans/modules/php/wordpress/validators/WordPressDirectoryNameValidatorTest.java

@@ -43,7 +43,7 @@
 
 import java.util.Arrays;
 import java.util.Collections;
-import junit.framework.Assert;
+import org.junit.Assert;
 import org.junit.Test;
 import org.netbeans.modules.php.api.validation.ValidationResult;