message: refactor: use optional chaining
diff: @@ -7,7 +7,7 @@ import { OperatorFunction, TeardownLogic } from '../types';
  * Used to determine if an object is an Observable with a lift function.
  */
  export function hasLift(source: any): source is { lift: InstanceType<typeof Observable>['lift'] } {
  - return source && typeof source.lift === 'function';
  + return typeof source?.lift === 'function';
  }
  /**
  