message: Create pending messages queue in scribes constructor
diff: @@ -45,7 +45,7 @@ export class ScribeLambda extends SequencedLambda {
  private pendingCheckpointMessages = new Deque<ISequencedOperationMessage>();
  // messages not yet included within protocolHandler
  - private pendingMessages = new Deque<ISequencedDocumentMessage>();
  + private readonly pendingMessages: Deque<ISequencedDocumentMessage>;
  // current sequence/msn of the last processed offset
  private sequenceNumber = 0;
  @@ -72,7 +72,8 @@ export class ScribeLambda extends SequencedLambda {
  this.minSequenceNumber = scribe.minimumSequenceNumber;
  // Filter messages in case they were not deleted after the last checkpoint.
  - this.pendingMessages.push(...messages
  + this.pendingMessages = new Deque<ISequencedDocumentMessage>(
  + messages
  .filter((message) => message.operation.sequenceNumber > scribe.protocolState.sequenceNumber)
  .map((message) => message.operation));
  }
  