Minor fix

Signed-off-by: Rishab Nahata <rnnahata@amazon.com>

server/src/main/java/org/opensearch/common/bytes/AbstractBytesReference.java

@@ -91,7 +91,7 @@ public String utf8ToString() {
             throw new IllegalStateException("UTF16 String size is " + len +
                 ", should be less than " + MAX_LENGTH);
         }
-        return toBytesRef().utf8ToString();
+        return bytesRef.utf8ToString();
     }
 
     @Override