Update stamp method in OtsCli.java

Serialise DetachedTimestampFile object instead of TimeStamp object in Stamp function to stamp digest

Author: RebekkalPangras

src/main/java/com/eternitywall/ots/OtsCli.java

@@ -315,7 +315,8 @@ private static void stamp(Hash hash, List<String> calendarsUrl, Integer m, Strin
         try {
             DetachedTimestampFile detached = DetachedTimestampFile.from(hash);
             Timestamp stampResult = OpenTimestamps.stamp(detached, calendarsUrl, m, privateUrls);
-            Files.write(path, stampResult.serialize());
+            DetachedTimestampFile detachedToSerialize = new DetachedTimestampFile(hash.getOp(), stampResult);
+            Files.write(path, detachedToSerialize.serialize());
             System.out.println("The timestamp proof '" + argsOts + "' has been created!");
         } catch (Exception e) {
             log.severe("Invalid shasum");