message: docs(README): use .json sytanx
diff: @@ -551,16 +551,16 @@ Jest support the feature of [snapshot testing](https://jestjs.io/docs/en/snapsho
  By the way, Jest built-in code coverage reports, the report files are generated in `./coverage` folder. You can configure `./package.json` to define which files that you want to cover. For example:
  -```
  +```json
  {
  // ...
  "jest": {
  "collectCoverageFrom": [
  "src/pages/**/*.tsx", // Define the files, which want to be covered
  "!src/pages/index.ts" // The files will be ignored by code coverage
  - ],
  + ]
  // Other configurations
  - },
  + }
  // ...
  }
  ```
  