Bump @vuepress/plugin-back-to-top from 1.8.2 to 1.9.5

Bumps [@vuepress/plugin-back-to-top](https://github.com/vuejs/vuepress/tree/HEAD/packages/@vuepress/plugin-back-to-top) from 1.8.2 to 1.9.5.
- [Release notes](https://github.com/vuejs/vuepress/releases)
- [Changelog](https://github.com/vuejs/vuepress/blob/master/CHANGELOG.md)
- [Commits](https://github.com/vuejs/vuepress/commits/v1.9.5/packages/@vuepress/plugin-back-to-top)

---
updated-dependencies:
- dependency-name: "@vuepress/plugin-back-to-top"
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

package-lock.json

@@ -28,7 +28,7 @@
     "eslint": "^8.1.0",
     "typescript": "4.2.4",
     "vuepress": "1.4.0",
-    "@vuepress/plugin-back-to-top": "^1.3.0",
+    "@vuepress/plugin-back-to-top": "^1.9.5",
     "@vuepress/plugin-google-analytics": "^1.9.5"
   }
 }