feat(xo-web/mirror): add the possibility to select vm backups

[MathieuRA]

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Description

Short explanation of this PR (feel free to re-use commit message)

Checklist

• Commit
  • Title follows commit conventions
  • Reference the relevant issue (Fixes #007, See xoa-support#42, See https://...)
  • If bug fix, add Introduced by
• Changelog
  • If visible by XOA users, add changelog entry
  • Update "Packages to release" in CHANGELOG.unreleased.md
• PR
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