Update Microsoft.CodeAnalysis.CSharp to 4.4.0.

Author: alexrp

Directory.Packages.props

@@ -18,7 +18,7 @@
         <PackageVersion Include="Microsoft.CodeAnalysis.BannedApiAnalyzers"
                         Version="3.3.3" />
         <PackageVersion Include="Microsoft.CodeAnalysis.CSharp"
-                        Version="4.3.1" />
+                        Version="4.4.0" />
         <PackageVersion Include="Microsoft.Extensions.Hosting"
                         Version="7.0.0" />
         <PackageVersion Include="Microsoft.Extensions.Hosting.Systemd"