docs: Update webpack.IgnorePlugin for web pack 5 (default in latest Next.js)

[MoOx]

Just got this

ValidationError: Invalid options object. Ignore Plugin has been initialized using an options object that does not match the API schema.
 - options should be one of these:
   object { resourceRegExp, contextRegExp? } | object { checkResource }
   Details:
    * options misses the property 'resourceRegExp'. Should be:
      RegExp
      -> A RegExp to test the request against.
    * options misses the property 'checkResource'. Should be:
      function
      -> A filter function for resource and context.
    at validate (~/node_modules/next/dist/compiled/schema-utils3/index.js:1:150822)
    at ~/node_modules/next/dist/compiled/webpack/bundle5.js:126431:17
    at new IgnorePlugin (~/node_modules/next/dist/compiled/webpack/bundle5.js:42929:3)
    at Object.webpack (~/next.config.js:46:27)
    at Object.webpack (~/node_modules/next-transpile-modules/src/next-transpile-modules.js:255:29)
    at Object.newWebpackFunction [as webpack] (~/node_modules/@sentry/nextjs/dist/config/webpack.js:40:40)
    at Object.getBaseWebpackConfig [as default] (~/node_modules/next/dist/build/webpack-config.js:1186:32)
    at async Promise.all (index 0)
    at async Span.traceAsyncFn (~/node_modules/next/dist/trace/trace.js:79:20)
    at async Span.traceAsyncFn (~/node_modules/next/dist/trace/trace.js:79:20) {
  errors: [
    {
      keyword: 'anyOf',
      dataPath: '',
      schemaPath: '#/anyOf',
      params: {},
      message: 'should match some schema in anyOf',
      schema: [Array],
      parentSchema: [Object],
      data: /lib\/server/,
      children: [Array]
    }
  ],
  schema: { title: 'IgnorePluginOptions', anyOf: [ [Object], [Object] ] },
  headerName: 'Ignore Plugin',
  baseDataPath: 'options',
  postFormatter: null
}

I checked official webpack docs: https://webpack.js.org/plugins/ignore-plugin/

[rrdelaney]

Thanks for the update! Sometimes it can be hard to ensure instructions like these are always up to date