Add missing test branch

Author: garydgregory

src/test/java/org/apache/commons/cli/UtilTest.java

@@ -23,8 +23,11 @@ Licensed to the Apache Software Foundation (ASF) under one or more
 import org.junit.jupiter.api.Test;
 
 public class UtilTest {
+
     @Test
     public void testStripLeadingAndTrailingQuotes() {
+        assertNull(Util.stripLeadingAndTrailingQuotes(null));
+        assertEquals("", Util.stripLeadingAndTrailingQuotes(""));
         assertEquals("foo", Util.stripLeadingAndTrailingQuotes("\"foo\""));
         assertEquals("foo \"bar\"", Util.stripLeadingAndTrailingQuotes("foo \"bar\""));
         assertEquals("\"foo\" bar", Util.stripLeadingAndTrailingQuotes("\"foo\" bar"));