message: remove Object.assign
diff: @@ -227,10 +227,11 @@ export class ParsedHtmlDocument extends ParsedDocument<ASTNode, HtmlVisitor> {
  const clonedDocContainingNode =
  this._findClonedContainingNode(astClone, docContainingNode);
  - const inlineStringifyOptions = Object.assign(
  - {},
  - options,
  - {indent: expectedIndentation, inlineDocuments: otherDocuments});
  + const inlineStringifyOptions = {
  + ...options,
  + indent: expectedIndentation,
  + inlineDocuments: otherDocuments
  + };
  const endingSpace =
  expectedIndentation ? ' '.repeat(expectedIndentation - 1) : '';
  