message: use common-utils assert over node assert
diff: * Licensed under the MIT License.
  */
  -import assert from "assert";
  +import { assert } from "@fluidframework/common-utils";
  import * as api from "@fluidframework/driver-definitions";
  import { IClient, IErrorTrackingService } from "@fluidframework/protocol-definitions";
  import { GitManager, Historian, ICredentials, IGitCache } from "@fluidframework/server-services-client";
  @@ -94,7 +94,7 @@ export class DocumentService implements api.IDocumentService {
  * @returns returns the document delta storage service for routerlicious driver.
  */
  public async connectToDeltaStorage(): Promise<api.IDocumentDeltaStorageService> {
  - assert(this.documentStorageService, "Storage service not initialized");
  + assert(!!this.documentStorageService, "Storage service not initialized");
  const deltaStorage = new DeltaStorageService(this.deltaStorageUrl, this.tokenProvider, this.logger);
  return new DocumentDeltaStorageService(this.tenantId, this.documentId,
  