Bump DeterminateSystems/magic-nix-cache-action from 2 to 3

Bumps [DeterminateSystems/magic-nix-cache-action](https://github.com/determinatesystems/magic-nix-cache-action) from 2 to 3.
- [Release notes](https://github.com/determinatesystems/magic-nix-cache-action/releases)
- [Commits](DeterminateSystems/magic-nix-cache-action@v2...v3)

---
updated-dependencies:
- dependency-name: DeterminateSystems/magic-nix-cache-action
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/ci-nix.yml

@@ -32,7 +32,7 @@ jobs:
     steps:
       - uses: actions/checkout@v4
       - uses: DeterminateSystems/nix-installer-action@v9
-      - uses: DeterminateSystems/magic-nix-cache-action@v2
+      - uses: DeterminateSystems/magic-nix-cache-action@v3
       - run: nix flake check
       - run: nix develop --command echo 'This step should be done before any other "nix develop" steps because of measuring Nix build time'
       - run: nix run .#console