ui: bump vee-validate from 4.12.6 to 4.12.8 in /ui

Bumps [vee-validate](https://github.com/logaretm/vee-validate/tree/HEAD/packages/vee-validate) from 4.12.6 to 4.12.8.
- [Release notes](https://github.com/logaretm/vee-validate/releases)
- [Changelog](https://github.com/logaretm/vee-validate/blob/main/packages/vee-validate/CHANGELOG.md)
- [Commits](https://github.com/logaretm/vee-validate/commits/v4.12.8/packages/vee-validate)

---
updated-dependencies:
- dependency-name: vee-validate
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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