chore(deps): bump nixpkgs from 2991645 to 64c08a7

Bumps [nixpkgs](https://github.com/NixOS/nixpkgs) from `2991645` to `64c08a7`.
- [Commits](NixOS/nixpkgs@2991645...64c08a7)

---
updated-dependencies:
- dependency-name: nixpkgs
  dependency-version: 64c08a7ca051951c8eae34e3e3cb1e202fe36786
  dependency-type: direct:production
...

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Author: dependabot[bot]