chore(deps): update dependency stylesharp.analyzers to 3.21.0

Author: renovate[bot]

src/Directory.Packages.props

@@ -25,7 +25,7 @@
     <PackageVersion Include="Splat.DryIoc" Version="$(SplatVersion)" />
     <PackageVersion Include="Splat.Microsoft.Extensions.DependencyInjection" Version="$(SplatVersion)" />
     <PackageVersion Include="Splat.Ninject" Version="$(SplatVersion)" />
-    <PackageVersion Include="StyleSharp.Analyzers" Version="3.17.9"/>
+    <PackageVersion Include="StyleSharp.Analyzers" Version="3.21.0"/>
     <PackageVersion Include="System.Collections.Immutable" Version="10.0.9" />
     <PackageVersion Include="System.IO.FileSystem.Primitives" Version="4.3.0" />
     <PackageVersion Include="System.Runtime.Serialization.Primitives" Version="4.3.0" />