chore(deps): update dependency system.reactive to v6 (#577)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

Directory.Packages.props

@@ -38,7 +38,7 @@
     <PackageVersion Include="Serilog.Sinks.File" Version="5.0.0" />
     <PackageVersion Include="StyleCop.Analyzers" Version="1.2.0-beta.435" />
     <PackageVersion Include="System.Memory" Version="4.5.5" />
-    <PackageVersion Include="System.Reactive" Version="5.0.0" />
+    <PackageVersion Include="System.Reactive" Version="6.0.0" />
     <PackageVersion Include="System.Runtime.Loader" Version="4.3.0" />
     <PackageVersion Include="System.Text.Json" Version="6.0.7" />
     <PackageVersion Include="System.Threading.Tasks.Dataflow" Version="7.0.0" />