message: Fix package.json command using yarn.
diff: "description": "SumUp's React UI component library",
  "main": "index.js",
  "scripts": {
  - "fix:prettier":
  - "prettier --config prettier.config.js --write src/**/*.js && prettier --config prettier.config.js --write stories/*.js",
  + "fix:prettier": "prettier --config prettier.config.js --write src/**/*.js && prettier --config prettier.config.js --write stories/*.js",
  "fix:eslint": "eslint --fix --quiet src/**/*.js",
  "fix:stylelint": "stylelint \"src/**/*.scss\" --cache --fix",
  "fix": "npm run fix:prettier; npm run fix:eslint; npm run fix:stylelint",
  - "test":
  - "npm run test:lint-js && npm run test:lint-css && npm run test:unit",
  - "test:lint-css:watch":
  - "onchange \"src/**/*.scss\" \"src/**/*.scss\" -- npm run test:lint-css",
  + "test": "npm run test:lint-js && npm run test:lint-css && npm run test:unit",
  + "test:lint-css:watch": "onchange \"src/**/*.scss\" \"src/**/*.scss\" -- npm run test:lint-css",
  "test:lint-css": "stylelint \"src/**/*.scss\" --cache",
  "test:lint-js": "eslint --cache --quiet src/**/*.js",
  "test:lint-js:watch": "onchange \"src/**/*.js\" -- npm run test:lint-js",
  "test:unit:watch": "npm run test:unit:output -- --watch",
  "test:unit:output": "jest --json --outputFile=jest-test-results.json",
  "prepush": "npm test",
  - "start": "yarn test:unit:output && start-storybook -p 6006",
  + "start": "npm run test:unit:output && start-storybook -p 6006",
  "prebuild": "npm run test:unit:output",
  "build": "build-storybook -c .storybook -o .out",
  "deploy": "storybook-to-ghpages"
  },
  "lint-staged": {
  - "*.js": ["npm run fix:prettier", "git add"]
  + "*.js": [
  + "npm run fix:prettier",
  + "git add"
  + ]
  },
  "repository": {
  "type": "git",
  