build(deps): update akavache requirement from 8.* to 9.* in /src (#278)

Updates the requirements on [akavache](https://github.com/reactiveui/akavache) to permit the latest version.
- [Release notes](https://github.com/reactiveui/akavache/releases)
- [Commits](reactiveui/Akavache@8.1.1...9.0.1)

---
updated-dependencies:
- dependency-name: akavache
  dependency-type: direct:production
...

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

src/Fusillade.Tests/Fusillade.Tests.csproj

@@ -13,7 +13,7 @@
 	</ItemGroup>
 
 	<ItemGroup>
-		<PackageReference Include="akavache" Version="8.*" />
+		<PackageReference Include="akavache" Version="9.*" />
 		<PackageReference Include="ReactiveUI.Testing" Version="18.*" />
 		<PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.2.0" />
 		<PackageReference Include="xunit" Version="2.4.1" />