Updating dart-dio dependency version

Author: aman-v-singh

codegens/dart-dio/package.json

@@ -27,7 +27,7 @@
   "license": "Apache-2.0",
   "homepage": "https://github.com/postmanlabs/code-generators/tree/master/codegens/dart-dio",
   "dependencies": {
-    "lodash": "^4.17.21"
+    "lodash": "4.17.21"
   },
   "devDependencies": {},
   "engines": {