chore(deps): update cachix/install-nix-action action to v27 (#123)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
|
[cachix/install-nix-action](https://togithub.com/cachix/install-nix-action)
| action | major | `v26` -> `v27` |

---

### Release Notes

<details>
<summary>cachix/install-nix-action (cachix/install-nix-action)</summary>

###
[`v27`](https://togithub.com/cachix/install-nix-action/releases/tag/v27)

[Compare
Source](https://togithub.com/cachix/install-nix-action/compare/v26...v27)

##### What's Changed

- Enable `always-allow-substitutes` by default by
[@&#8203;sandydoo](https://togithub.com/sandydoo) in
[https://github.com/cachix/install-nix-action/pull/207](https://togithub.com/cachix/install-nix-action/pull/207)
- nix: 2.20.5 -> 2.22.1 by [@&#8203;kashw2](https://togithub.com/kashw2)
in
[https://github.com/cachix/install-nix-action/pull/206](https://togithub.com/cachix/install-nix-action/pull/206)
- ci: fix tests by [@&#8203;sandydoo](https://togithub.com/sandydoo) in
[https://github.com/cachix/install-nix-action/pull/208](https://togithub.com/cachix/install-nix-action/pull/208)

##### New Contributors

- [@&#8203;kashw2](https://togithub.com/kashw2) made their first
contribution in
[https://github.com/cachix/install-nix-action/pull/206](https://togithub.com/cachix/install-nix-action/pull/206)

**Full Changelog**:
cachix/install-nix-action@v26...V27

</details>

---

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---

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---

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.github/workflows/check.yml

@@ -20,7 +20,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     steps:
       - name: Install Nix
-        uses: cachix/install-nix-action@v26
+        uses: cachix/install-nix-action@v27
       - uses: cachix/cachix-action@v15
         with:
           name: nixpkgs-ruby

.github/workflows/update.yml

@@ -16,7 +16,7 @@ jobs:
       with:
           ref: master
     - name: Install Nix
-      uses: cachix/install-nix-action@v26
+      uses: cachix/install-nix-action@v27
     - run: nix run .#update
       env:
         GITHUB_TOKEN: ${{secrets.GITHUB_TOKEN}}