docs: public Map<String, MissingRevisions> revsDiff(Map<String, Set<String>> revisions) {
          Misc.checkNotNull(revisions, "Input revisions");
          URI uri = this.uriHelper.revsDiffUri();
          String payload = JSONUtils.toJson(revisions);
  
          HttpConnection connection = Http.POST(uri, "application/json");
          connection.setRequestBody(payload);
          return executeToJsonObjectWithRetry(connection, JSONUtils.STRING_MISSING_REVS_MAP_TYPE_DEF);
      }