fix(deps): bump nuxt from 2.13.3 to 2.15.8

Bumps [nuxt](https://github.com/nuxt/nuxt.js) from 2.13.3 to 2.15.8.
- [Release notes](https://github.com/nuxt/nuxt.js/releases)
- [Changelog](https://github.com/nuxt/nuxt.js/blob/dev/RELEASE_PLAN.md)
- [Commits](nuxt/nuxt@v2.13.3...v2.15.8)

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

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

Author: dependabot[bot]

package.json

@@ -32,7 +32,7 @@
     "@nuxtjs/robots": "^2.5.0",
     "@nuxtjs/sitemap": "^2.4.0",
     "@tailwindcss/typography": "^0.2.0",
-    "nuxt": "^2.13",
+    "nuxt": "^2.15",
     "nuxt-i18n": "^6.26.0",
     "nuxt-trailingslash-module": "^1.1.0",
     "responsive-loader": "^1.2.0",