Bump SixLabors.ImageSharp from 3.1.4 to 3.1.5 in /Extensions/ImageOutput

Bumps [SixLabors.ImageSharp](https://github.com/SixLabors/ImageSharp) from 3.1.4 to 3.1.5.
- [Release notes](https://github.com/SixLabors/ImageSharp/releases)
- [Commits](SixLabors/ImageSharp@v3.1.4...v3.1.5)

---
updated-dependencies:
- dependency-name: SixLabors.ImageSharp
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

Extensions/ImageOutput/ImageOutput.csproj

@@ -15,7 +15,7 @@
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
-    <PackageReference Include="SixLabors.ImageSharp" Version="3.1.4" />
+    <PackageReference Include="SixLabors.ImageSharp" Version="3.1.5" />
   </ItemGroup>
 
   <ItemGroup>