build(deps): bump ReactiveUI from 16.2.1 to 16.2.6 in /src (#765)

Bumps [ReactiveUI](https://github.com/reactiveui/reactiveui) from 16.2.1 to 16.2.6.
- [Release notes](https://github.com/reactiveui/reactiveui/releases)
- [Commits](reactiveui/ReactiveUI@16.2.1...16.2.6)

---
updated-dependencies:
- dependency-name: ReactiveUI
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

src/ReactiveUI.DI.Tests/ReactiveUI.DI.Tests.csproj

@@ -47,7 +47,7 @@
   </Choose>
 
   <ItemGroup>
-    <PackageReference Include="ReactiveUI" Version="16.2.1" />
+    <PackageReference Include="ReactiveUI" Version="16.2.6" />
   </ItemGroup>
 
 </Project>