chore(deps): update cachix/install-nix-action action to v31 (#105)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
|
[cachix/install-nix-action](https://redirect.github.com/cachix/install-nix-action)
| action | major | `v27` -> `v31` |

---

### Release Notes

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

###
[`v31`](https://redirect.github.com/cachix/install-nix-action/releases/tag/v31)

[Compare
Source](https://redirect.github.com/cachix/install-nix-action/compare/v30...v31)

#### What's Changed

- nix: 2.24.9 -> 2.25.2 by
[@&#8203;Mic92](https://redirect.github.com/Mic92) in
[https://github.com/cachix/install-nix-action/pull/218](https://redirect.github.com/cachix/install-nix-action/pull/218)
- ci: fix latest installer tests by
[@&#8203;sandydoo](https://redirect.github.com/sandydoo) in
[https://github.com/cachix/install-nix-action/pull/220](https://redirect.github.com/cachix/install-nix-action/pull/220)
- ci: add ubuntu-24.04-arm to matrix by
[@&#8203;msgilligan](https://redirect.github.com/msgilligan) in
[https://github.com/cachix/install-nix-action/pull/221](https://redirect.github.com/cachix/install-nix-action/pull/221)
- nix: 2.25.2 -> 2.26.2 by
[@&#8203;Mic92](https://redirect.github.com/Mic92) in
[https://github.com/cachix/install-nix-action/pull/226](https://redirect.github.com/cachix/install-nix-action/pull/226)

#### New Contributors

- [@&#8203;msgilligan](https://redirect.github.com/msgilligan) made
their first contribution in
[https://github.com/cachix/install-nix-action/pull/221](https://redirect.github.com/cachix/install-nix-action/pull/221)

**Full Changelog**:
https://github.com/cachix/install-nix-action/compare/v30...v31

###
[`v30`](https://redirect.github.com/cachix/install-nix-action/releases/tag/v30)

[Compare
Source](https://redirect.github.com/cachix/install-nix-action/compare/v29...v30)

- Nix: 2.24.7 -> 2.24.9, fixing
[GHSA-6fjr-mq49-mm2c](https://redirect.github.com/NixOS/nix/security/advisories/GHSA-6fjr-mq49-mm2c)

###
[`v29`](https://redirect.github.com/cachix/install-nix-action/releases/tag/v29)

[Compare
Source](https://redirect.github.com/cachix/install-nix-action/compare/v27...v29)

Bumps Nix to
[2.24.7](https://nix.dev/manual/nix/2.24/release-notes/rl-2.24)

</details>

---

### Configuration

📅 **Schedule**: Branch creation - At any time (no schedule defined),
Automerge - At any time (no schedule defined).

🚦 **Automerge**: Disabled by config. Please merge this manually once you
are satisfied.

♻ **Rebasing**: Whenever PR is behind base branch, or you tick the
rebase/retry checkbox.

🔕 **Ignore**: Close this PR and you won't be reminded about this update
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---

- [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check
this box

---

This PR was generated by [Mend Renovate](https://mend.io/renovate/).
View the [repository job
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<!--renovate-debug:eyJjcmVhdGVkSW5WZXIiOiIzOS4xODUuNCIsInVwZGF0ZWRJblZlciI6IjM5LjE4NS40IiwidGFyZ2V0QnJhbmNoIjoibWFpbiIsImxhYmVscyI6W119-->

.github/workflows/nix.yml

@@ -15,7 +15,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4
-      - uses: cachix/install-nix-action@v27
+      - uses: cachix/install-nix-action@v31
         with:
           extra_nix_config: |
             access-tokens = github.com=${{ github.token }}
@@ -35,7 +35,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4
-      - uses: cachix/install-nix-action@v27
+      - uses: cachix/install-nix-action@v31
         with:
           extra_nix_config: |
             access-tokens = github.com=${{ github.token }}
@@ -55,7 +55,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4
-      - uses: cachix/install-nix-action@v27
+      - uses: cachix/install-nix-action@v31
         with:
           extra_nix_config: |
             access-tokens = github.com=${{ github.token }}