chore(deps): bump xunit from 2.7.1 to 2.8.1 (#89)

Bumps [xunit](https://github.com/xunit/xunit) from 2.7.1 to 2.8.1.
<details>
<summary>Commits</summary>
<ul>
<li><a
href="https://github.com/xunit/xunit/commit/ba2ae9bc859840c9b48cd668c2d2818b8f049457"><code>ba2ae9b</code></a>
v2.8.1</li>
<li><a
href="https://github.com/xunit/xunit/commit/151b8d0d9fc63051ea224cd83f61d8b49e0fb3a0"><code>151b8d0</code></a>
Use 'dotnet format' instead of 'dotnet dotnet-format'</li>
<li><a
href="https://github.com/xunit/xunit/commit/be6db6f41069c22068540511779a0ddefa05cc20"><code>be6db6f</code></a>
<a href="https://redirect.github.com/xunit/xunit/issues/2931">#2931</a>:
Tighten up types to prevent accidentically calling AddOrGet with a
Con...</li>
<li><a
href="https://github.com/xunit/xunit/commit/f466d81ad9f88486990c8100eaab4e28b0db94bf"><code>f466d81</code></a>
<a href="https://redirect.github.com/xunit/xunit/issues/2927">#2927</a>:
Misleading error message when class used in IClassFixture&lt;&gt; throws
exc...</li>
<li><a
href="https://github.com/xunit/xunit/commit/1911ea7708f7f939add4d124c7b7e76c7a3cd972"><code>1911ea7</code></a>
Missed unit test updates</li>
<li><a
href="https://github.com/xunit/xunit/commit/f497d65ec5b3f7780d1f7034b2725d40da31daea"><code>f497d65</code></a>
Cannot use full assembly path as dictionary key for execution options
lookup,...</li>
<li><a
href="https://github.com/xunit/xunit/commit/c2f2d47ec00d1dfc408bacced12f96647a2f695f"><code>c2f2d47</code></a>
Add ability to provide live output messages from running tests</li>
<li><a
href="https://github.com/xunit/xunit/commit/013093b7e2627c3a025a828d2cf253c3cadd29c4"><code>013093b</code></a>
Polyfill in StringSyntaxAttribute</li>
<li><a
href="https://github.com/xunit/xunit/commit/e1e4c2e23648de2dc5ccf4a9b8c9608ca5f7bcee"><code>e1e4c2e</code></a>
<a href="https://redirect.github.com/xunit/xunit/issues/2719">#2719</a>:
Class with custom Fact with throwing Skip should fail appropriately</li>
<li><a
href="https://github.com/xunit/xunit/commit/8b0b13ca02e8bd737f1f2394b5f4e5c77a37cf5e"><code>8b0b13c</code></a>
Clarify naming</li>
<li>Additional commits viewable in <a
href="https://github.com/xunit/xunit/compare/2.7.1...2.8.1">compare
view</a></li>
</ul>
</details>
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test/Extism.Sdk/Extism.Sdk.Tests.csproj

@@ -12,7 +12,7 @@
     <PackageReference Include="Extism.runtime.all" Version="1.2.0" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.10.0" />
     <PackageReference Include="Shouldly" Version="4.2.1" />
-    <PackageReference Include="xunit" Version="2.7.1" />
+    <PackageReference Include="xunit" Version="2.8.1" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.8.1">
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
       <PrivateAssets>all</PrivateAssets>