chore(deps-dev): bump prettier from 2.8.4 to 2.8.7

Bumps [prettier](https://github.com/prettier/prettier) from 2.8.4 to 2.8.7.
- [Release notes](https://github.com/prettier/prettier/releases)
- [Changelog](https://github.com/prettier/prettier/blob/main/CHANGELOG.md)
- [Commits](prettier/prettier@2.8.4...2.8.7)

---
updated-dependencies:
- dependency-name: prettier
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

package-lock.json

@@ -20,7 +20,7 @@
     "markdown-it-imsize": "^2.0.1",
     "markdown-it-task-lists": "^2.1.1",
     "markdown-it-video": "^0.6.3",
-    "prettier": "^2.8.4",
+    "prettier": "^2.8.7",
     "stylus-supremacy": "^2.17.3",
     "vuepress": "^1.9.9",
     "vuepress-plugin-canonical": "^1.0.0",