message: Fix - react: checkbox column is editable for readonly matrix if showInMultipleColumns is true
diff: import * as React from "react";
  -import { ReactSurveyElement, SurveyQuestionElementBase } from "./reactquestion_element";
  +import {
  + ReactSurveyElement,
  + SurveyQuestionElementBase,
  +} from "./reactquestion_element";
  import { SurveyQuestion, SurveyQuestionAndErrorsCell } from "./reactquestion";
  import {
  MatrixDropdownRowModelBase,
  @@ -132,7 +135,11 @@ export class SurveyQuestionMatrixDropdownBase extends SurveyQuestionElementBase
  matrixrow.push(this.renderCell(cells[i], i, cssClasses));
  }
  var key = "row" + keyValue;
  - return <tr className={row.className} key={key}>{matrixrow}</tr>;
  + return (
  + <tr className={row.className} key={key}>
  + {matrixrow}
  + </tr>
  + );
  }
  renderCell(
  cell: QuestionMatrixDropdownRenderedCell,
  @@ -316,7 +323,7 @@ export class SurveyQuestionMatrixDropdownCell extends SurveyQuestionAndErrorsCel
  key={key}
  question={this.cell.question}
  cssClasses={this.cell.question.cssClasses}
  - isDisplayMode={this.cell.question.isDisplayMode}
  + isDisplayMode={this.cell.question.isReadOnly}
  item={this.cell.item}
  isFirst={this.cell.isFirstChoice}
  index={this.cell.choiceIndex.toString()}
  @@ -331,7 +338,7 @@ export class SurveyQuestionMatrixDropdownCell extends SurveyQuestionAndErrorsCel
  key={key}
  question={this.cell.question}
  cssClasses={this.cell.question.cssClasses}
  - isDisplayMode={this.cell.question.isDisplayMode}
  + isDisplayMode={this.cell.question.isReadOnly}
  item={this.cell.item}
  index={this.cell.choiceIndex.toString()}
  isChecked={this.cell.question.value === this.cell.item.value}
  