replacing bit faster version of empty check

Author: ameyjadiye

src/main/java/org/apache/commons/text/similarity/SorensenDicesSimilarity.java

@@ -85,7 +85,7 @@ public Double apply(final CharSequence left, final CharSequence right) {
             return 1d;
         }
 
-        if ("".equals(left) || "".equals(right)) {
+        if (left.length() == 0 || right.length() == 0) {
             return 0d;
         }
 

src/test/java/org/apache/commons/text/similarity/SorensenDicesSimilarityTest.java

@@ -43,6 +43,8 @@ public void test() {
     public void testGetSorensenDicesSimilarity_StringString() {
 
         assertEquals(1d, similarity.apply("", ""));
+        assertEquals(0d, similarity.apply("", "a"));
+        assertEquals(0d, similarity.apply("a", ""));
         assertEquals(1.0d, similarity.apply("foo", "foo"));
         assertEquals(0.8d, similarity.apply("foo", "foo "));
         assertEquals(0.4d, similarity.apply("frog", "fog"));