update ktchn package json with missing types

ktchn/package.json

@@ -12,6 +12,7 @@
     "@types/chai": "^4.1.7",
     "@types/cheerio": "^0.22.9",
     "@types/cookie-parser": "^1.4.1",
+    "@types/dotenv": "^6.1.1",
     "@types/express": "^4.16.0",
     "@types/jest": "^23.3.12",
     "@types/mongodb": "^3.1.19",