⬆️ Bump cachix/install-nix-action from 24 to 25 (#5032)

Bumps [cachix/install-nix-action](https://github.com/cachix/install-nix-action) from 24 to 25.
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a href="https://github.com/cachix/install-nix-action/releases">cachix/install-nix-action's releases</a>.</em></p>
<blockquote>
<h2>install-nix-action-v25</h2>
<p>Nix 2.19.2</p>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a href="6004951b18"><code>6004951</code></a> Nix: 2.19.1 -&gt; 2.19.2</li>
<li>See full diff in <a href="https://github.com/cachix/install-nix-action/compare/v24...v25">compare view</a></li>
</ul>
</details>
<br />


[![Dependabot compatibility score](https://dependabot-badges.githubapp.com/badges/compatibility_score?dependency-name=cachix/install-nix-action&package-manager=github_actions&previous-version=24&new-version=25)](https://docs.github.com/en/github/managing-security-vulnerabilities/about-dependabot-security-updates#about-compatibility-scores)

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</details>

.github/workflows/ci.yml

@@ -492,7 +492,7 @@ jobs:
 
       # I could not find a way to install tree-grepper without nix
       # https://github.com/BrianHicks/tree-grepper/issues/293
-      - uses: cachix/install-nix-action@v24
+      - uses: cachix/install-nix-action@v25
       - uses: cachix/cachix-action@v13
         with:
             name: tree-grepper