Bump unhead and @unhead/vue

Bumps [unhead](https://github.com/unjs/unhead/tree/HEAD/packages/unhead) and [@unhead/vue](https://github.com/unjs/unhead/tree/HEAD/packages/vue). These dependencies needed to be updated together.

Updates `unhead` from 2.0.0-rc.13 to 2.1.12
- [Release notes](https://github.com/unjs/unhead/releases)
- [Commits](https://github.com/unjs/unhead/commits/v2.1.12/packages/unhead)

Updates `@unhead/vue` from 2.0.0-rc.13 to 2.1.12
- [Release notes](https://github.com/unjs/unhead/releases)
- [Commits](https://github.com/unjs/unhead/commits/v2.1.12/packages/vue)

---
updated-dependencies:
- dependency-name: unhead
  dependency-version: 2.1.12
  dependency-type: indirect
- dependency-name: "@unhead/vue"
  dependency-version: 2.1.12
  dependency-type: indirect
...

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

Author: dependabot[bot]