chore(deps-dev): bump @tiptap/extension-placeholder (#667)

Bumps [@tiptap/extension-placeholder](https://github.com/ueberdosis/tiptap/tree/HEAD/packages/extension-placeholder) from 2.0.0-beta.220 to 2.0.0.
- [Release notes](https://github.com/ueberdosis/tiptap/releases)
- [Changelog](https://github.com/ueberdosis/tiptap/blob/develop/packages/extension-placeholder/CHANGELOG.md)
- [Commits](https://github.com/ueberdosis/tiptap/commits/v2.0.0/packages/extension-placeholder)

---
updated-dependencies:
- dependency-name: "@tiptap/extension-placeholder"
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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package.json

@@ -76,7 +76,7 @@
     "@reduxjs/toolkit": "^1.9.3",
     "@tiptap/extension-image": "^2.0.0-beta.220",
     "@tiptap/extension-link": "^2.0.0",
-    "@tiptap/extension-placeholder": "^2.0.0-beta.220",
+    "@tiptap/extension-placeholder": "^2.0.0",
     "@tiptap/pm": "^2.0.0-beta.220",
     "@tiptap/react": "^2.0.0",
     "@tiptap/starter-kit": "^2.0.0-beta.220",