update-nixpkgs: update for the new fc-release-tools versions

[leona-ya]

This version sends matrix notifications on graceful failures and hard-resets nixpkgs with a safety belt instead of rebasing. This fixes the problems when a manual rebase conflict resolution is required.

PL-133100

Note

Requires flyingcircusio/fc-nixos-release-tools#3

Requires MATRIX_HOOKSHOT_URL in secrets to be set.

@flyingcircusio/release-managers

Release process

• Created changelog entry using ./changelog.sh

PR release workflow (internal)

• PR has internal ticket
• internal issue ID (PL-…) part of branch name
• internal issue ID mentioned in PR description text
• ticket is on Platform agile board
• ticket state set to Pull request ready
• if ticket is more urgent than within the next few days, directly contact a member of the Platform team

Design notes

• Provide a feature toggle if the change might need to be adjusted/reverted quickly depending on context. Consider whether the default should be on or off. Example: rate limiting.
• All customer-facing features and (NixOS) options need to be discoverable from documentation. Add or update relevant documentation such that hosted and guided customers can understand it as well.

Security implications

• Security requirements defined? (WHERE)
  • Should work in these scenarios:
    • Normal: No merge conflict, straight forward rebase
    • Conflict: Send notification, don't create PR
    • Moved nixpkgs while PR open: reject hard-rebase
• Security requirements tested? (EVIDENCE)
  • Tested in fc-nixos-testing