build(deps): bump autoprefixer from 10.3.7 to 10.4.0 (#9766)

Bumps [autoprefixer](https://github.com/postcss/autoprefixer) from 10.3.7 to 10.4.0.
- [Release notes](https://github.com/postcss/autoprefixer/releases)
- [Changelog](https://github.com/postcss/autoprefixer/blob/main/CHANGELOG.md)
- [Commits](https://github.com/postcss/autoprefixer/compare/10.3.7...10.4.0)

---
updated-dependencies:
- dependency-name: autoprefixer
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

packages/vant-cli/package.json

@@ -56,7 +56,7 @@
     "@vitejs/plugin-vue-jsx": "^1.2.0",
     "@vue/babel-plugin-jsx": "^1.1.1",
     "@vue/test-utils": "2.0.0-rc.14",
-    "autoprefixer": "^10.3.7",
+    "autoprefixer": "^10.4.0",
     "babel-jest": "^27.3.1",
     "clean-css": "^5.2.2",
     "commander": "^8.3.0",