build: use yarn instead of npm for lint/test script

Author: TheAlexLichter

package.json

@@ -14,7 +14,7 @@
   },
   "scripts": {
     "lint": "eslint lib test",
-    "test": "npm run lint && jest",
+    "test": "yarn lint && jest",
     "release": "standard-version && git push --follow-tags && npm publish",
     "commitlint": "commitlint -e $GIT_PARAMS",
     "coverage": "codecov"