Bump SixLabors.ImageSharp from 3.1.12 to 4.1.2

---
updated-dependencies:
- dependency-name: SixLabors.ImageSharp
  dependency-version: 4.1.2
  dependency-type: direct:production
...

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

Author: dependabot[bot]

ImageSharpCompare/ImageSharpCompare.csproj

@@ -44,7 +44,7 @@
 	</ItemGroup>
 
 	<ItemGroup>
-		<PackageReference Include="SixLabors.ImageSharp" Version="3.1.12" />
+		<PackageReference Include="SixLabors.ImageSharp" Version="4.1.2" />
 		<PackageReference Include="SonarAnalyzer.CSharp" Version="10.15.0.120848">
 			<PrivateAssets>all</PrivateAssets>
 			<IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>