Add package for Ubuntu 26.04 (resolute)
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### Summary
The latest LTS version of Ubuntu (26.04/resolute) has just been released. It would be good to have GitLab packages built for it as people start upgrading (in the meantime the noble packages seem to work fine).
### Proposal
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- Provide packages for Ubuntu 26.04 resolute.
### References
Equivalent proposal from 24.04: https://gitlab.com/gitlab-org/omnibus-gitlab/-/work_items/8509
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