add webpack as a peer dependency and roll back to webpack 4 types

Author: lobsterkatie

packages/nextjs/package.json

@@ -28,14 +28,15 @@
   },
   "devDependencies": {
     "@sentry/types": "6.13.3",
-    "@types/webpack": "^5.28.0",
+    "@types/webpack": "^4.41.31",
     "eslint": "7.20.0",
     "next": "10.1.3",
     "rimraf": "3.0.2"
   },
   "peerDependencies": {
     "next": "^10.0.8 || ^11.0",
-    "react": "15.x || 16.x || 17.x"
+    "react": "15.x || 16.x || 17.x",
+    "webpack": ">= 4.0.0"
   },
   "scripts": {
     "build": "run-p build:esm build:es5",