build(deps): bump cachix/cachix-action from 14 to 16 (#35)

Bumps [cachix/cachix-action](https://github.com/cachix/cachix-action) from 14 to 16.
- [Release notes](https://github.com/cachix/cachix-action/releases)
- [Commits](cachix/cachix-action@v14...v16)

---
updated-dependencies:
- dependency-name: cachix/cachix-action
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/docgen.yml

@@ -12,7 +12,7 @@ jobs:
     steps:
       - uses: actions/checkout@v4
       - uses: cachix/install-nix-action@v30
-      - uses: cachix/cachix-action@v14
+      - uses: cachix/cachix-action@v16
         with:
           name: mrcjkb
           authToken: '${{ secrets.CACHIX_AUTH_TOKEN }}'