chore(deps): bump cachix/cachix-action from 15 to 16 (#43)

Bumps [cachix/cachix-action](https://github.com/cachix/cachix-action) from 15 to 16.
- [Release notes](https://github.com/cachix/cachix-action/releases)
- [Commits](cachix/cachix-action@v15...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/build.yml

@@ -40,7 +40,7 @@ jobs:
         uses: DeterminateSystems/nix-installer-action@v16
       - name: 'Setup the Nix Cache'
         uses: DeterminateSystems/flakehub-cache-action@v1
-      - uses: cachix/cachix-action@v15
+      - uses: cachix/cachix-action@v16
         with:
           name: opentelemetry
           authToken: '${{ secrets.CACHIX_AUTH_TOKEN }}'