fix(jackson): decode short strings as UTF-8

Author: sean0407

msgpack-jackson/src/main/java/org/msgpack/jackson/dataformat/MessagePackParser.java

@@ -174,7 +174,7 @@ private String unpackString(MessageUnpacker messageUnpacker) throws IOException
                 return new String(tempChars, 0, strLen);
             }
             else {
-                return new String(tempBytes, 0, strLen);
+                return new String(tempBytes, 0, strLen, StandardCharsets.UTF_8);
             }
         }
         else {

msgpack-jackson/src/test/java/org/msgpack/jackson/dataformat/MessagePackDataformatForPojoTest.java

@@ -94,6 +94,16 @@ public void testStrings()
         assertEquals(stringPojo.longMultiByte, value.longMultiByte);
     }
 
+    @Test
+    public void testUnicodeStringRoundTrip()
+            throws IOException
+    {
+        String original = "çÇğĞıİöÖşŞüÜ";
+        byte[] bytes = objectMapper.writeValueAsBytes(original);
+        String value = objectMapper.readValue(bytes, String.class);
+        assertEquals(original, value);
+    }
+
     @Test
     public void testUsingCustomConstructor()
             throws IOException