chore(deps): update dependency espurify to v3

Author: renovate[bot]

package-lock.json

@@ -22,7 +22,7 @@
     "acorn": "^7.4.1",
     "eslint": "^6.8.0",
     "eslint-config-teppeis": "^10.3.1",
-    "espurify": "^2.0.1",
+    "espurify": "^3.1.0",
     "mocha": "^7.2.0",
     "prettier": "1.19.1"
   },