chore: add repository.directory field to each package.json to specify where each package lives in a monorepo (#3397)

Author: visualfanatic

package.json

@@ -8,7 +8,8 @@
   },
   "repository": {
     "type": "git",
-    "url": "git+https://github.com/vuejs/vue-cli.git"
+    "url": "git+https://github.com/vuejs/vue-cli.git",
+    "directory": "packages/@vue/eslint-config-prettier"
   },
   "keywords": [
     "vue",