build(deps): bump buildbot-nix from c989cad to d193d37

Bumps [buildbot-nix](https://github.com/nix-community/buildbot-nix) from `c989cad` to `d193d37`.
- [Release notes](https://github.com/nix-community/buildbot-nix/releases)
- [Commits](nix-community/buildbot-nix@c989cad...d193d37)

---
updated-dependencies:
- dependency-name: buildbot-nix
  dependency-version: d193d375fe5c4be29f13dc34552903cae6813b07
  dependency-type: direct:production
...

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Author: dependabot[bot]