add access public to all packages [skip ci] (#8573)

If people copy paste to make an new package they might miss this and we will get a publish error later so figured we should add it to all.

packages/babel-plugin-proposal-json-strings/package.json

@@ -4,6 +4,9 @@
   "description": "Escape U+2028 LINE SEPARATOR and U+2029 PARAGRAPH SEPARATOR in JS strings",
   "repository": "https://github.com/babel/babel/tree/master/packages/babel-plugin-proposal-json-strings",
   "license": "MIT",
+  "publishConfig": {
+    "access": "public"
+  },
   "main": "lib/index.js",
   "keywords": [
     "babel-plugin"