configureToolbarBlockOptions(toolbarConfig) {
    const { blockButtons } = this.props;
    return toolbarConfig && toolbarConfig.block
      ? toolbarConfig.block.map(type => blockButtons.find(button => button.style === type))
        .filter(button => button !== undefined)
      : blockButtons;
  }
Override which text modifications are available according BLOCK_BUTTONS style property.
Defaults all of them if no toolbarConfig.block passed:
  block: ['ordered-list-item', 'unordered-list-item', 'blockquote', 'header-three', 'todo'],
Example parameter: toolbarConfig = {
  block: ['ordered-list-item', 'unordered-list-item'],
  inline: ['BOLD', 'ITALIC', 'UNDERLINE', 'hyperlink'],
};