chore(deps): update eslint and prettier

Author: renovate-bot

package-lock.json

@@ -21,10 +21,10 @@
   "devDependencies": {
     "acorn": "^7.1.1",
     "eslint": "^6.8.0",
-    "eslint-config-teppeis": "^10.3.1",
+    "eslint-config-teppeis": "^11.0.1",
     "espurify": "^2.0.1",
     "mocha": "^7.1.1",
-    "prettier": "1.19.1"
+    "prettier": "2.0.1"
   },
   "homepage": "https://github.com/teppeis/empower-assert",
   "repository": {