Bump google/osv-scanner-action from 1.8.3 to 1.8.4 (flutter/engine#54797)

Bumps [google/osv-scanner-action](https://github.com/google/osv-scanner-action) from 1.8.3 to 1.8.4.
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a href="https://github.com/google/osv-scanner-action/releases">google/osv-scanner-action's releases</a>.</em></p>
<blockquote>
<h2>v1.8.4</h2>
<p>Bump OSV-Scanner version <a href="https://github.com/google/osv-scanner/releases/tag/v1.8.4">https://github.com/google/osv-scanner/releases/tag/v1.8.4</a></p>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a href="678a866dcb"><code>678a866</code></a> Merge pull request <a href="https://redirect.github.com/google/osv-scanner-action/issues/39">#39</a> from google/update-to-v1.8.4</li>
<li><a href="6a315dbacc"><code>6a315db</code></a> Update unified workflow example to point to v1.8.4 reusable workflows</li>
<li><a href="712a57b5f0"><code>712a57b</code></a> Update reusable workflows to point to v1.8.4 actions</li>
<li><a href="fa6b699964"><code>fa6b699</code></a> Update actions to use v1.8.4 osv-scanner image</li>
<li><a href="b756d11dcf"><code>b756d11</code></a> Merge pull request <a href="https://redirect.github.com/google/osv-scanner-action/issues/30">#30</a> from google/update-script</li>
<li><a href="c63eeb74bc"><code>c63eeb7</code></a> Big multiline string</li>
<li><a href="dd8ff8fe0e"><code>dd8ff8f</code></a> Fix string format</li>
<li><a href="336764a25a"><code>336764a</code></a> Merge pull request <a href="https://redirect.github.com/google/osv-scanner-action/issues/38">#38</a> from google/renovate_ignore</li>
<li><a href="ff89c57971"><code>ff89c57</code></a> Update package name</li>
<li><a href="12abe438b3"><code>12abe43</code></a> chore: disable renovate bot updating osv-scanner-action package.</li>
<li>Additional commits viewable in <a href="https://github.com/google/osv-scanner-action/compare/v1.8.3...v1.8.4">compare view</a></li>
</ul>
</details>
<br />

[![Dependabot compatibility score](https://dependabot-badges.githubapp.com/badges/compatibility_score?dependency-name=google/osv-scanner-action&package-manager=github_actions&previous-version=1.8.3&new-version=1.8.4)](https://docs.github.com/en/github/managing-security-vulnerabilities/about-dependabot-security-updates#about-compatibility-scores)

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</details>

engine/src/flutter/.github/workflows/third_party_scan.yml

@@ -41,7 +41,7 @@ jobs:
     name: Vulnerability scanning
     needs:
       extract-deps
-    uses: "google/osv-scanner-action/.github/workflows/osv-scanner-reusable.yml@v1.8.3"
+    uses: "google/osv-scanner-action/.github/workflows/osv-scanner-reusable.yml@v1.8.4"
     with:
       # Download the artifact uploaded in extract-deps step
       download-artifact: osv-lockfile-${{github.sha}}