feat: add yarn v2 (berry) support (#820)

* add json5 to deps

* pin version

* change version identifier

* some version experiments

* remove yarn.lock

Author: mathe42

packages/content/package.json

@@ -30,6 +30,7 @@
     "hookable": "^4.4.1",
     "html-tags": "^3.1.0",
     "js-yaml": "4.0.0",
+    "json5": "^2.2.0",
     "mdast-util-to-hast": "^10.2.0",
     "mkdirp": "^1.0.4",
     "node-req": "^2.1.2",