Bump Microsoft.Extensions.Configuration.EnvironmentVariables and Micr…

…osoft.Extensions.Configuration

Bumps [Microsoft.Extensions.Configuration.EnvironmentVariables](https://github.com/dotnet/runtime) and Microsoft.Extensions.Configuration. These dependencies needed to be updated together.

Updates `Microsoft.Extensions.Configuration.EnvironmentVariables` from 7.0.0 to 8.0.0
- [Release notes](https://github.com/dotnet/runtime/releases)
- [Commits](dotnet/runtime@v7.0.0...v8.0.0)

Updates `Microsoft.Extensions.Configuration` from 7.0.0 to 8.0.0

---
updated-dependencies:
- dependency-name: Microsoft.Extensions.Configuration.EnvironmentVariables
  dependency-type: direct:production
  update-type: version-update:semver-major
- dependency-name: Microsoft.Extensions.Configuration
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

src/Akka.Hosting.Tests/Akka.Hosting.Tests.csproj

@@ -5,7 +5,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="7.0.0" />
-    <PackageReference Include="Microsoft.Extensions.Configuration.EnvironmentVariables" Version="7.0.0" />
+    <PackageReference Include="Microsoft.Extensions.Configuration.EnvironmentVariables" Version="8.0.0" />
     <PackageReference Include="Akka.TestKit.Xunit2" Version="$(AkkaVersion)" />
     <PackageReference Include="FluentAssertions" Version="6.12.0" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="$(TestSdkVersion)" />