build(deps): bump MediatR in /services/FilterLists.AppHost

Bumps [MediatR](https://github.com/jbogard/MediatR) from 12.4.0 to 12.4.1.
- [Release notes](https://github.com/jbogard/MediatR/releases)
- [Commits](jbogard/MediatR@v12.4.0...v12.4.1)

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

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

services/Directory/FilterLists.Directory.Application/FilterLists.Directory.Application.csproj

@@ -17,7 +17,7 @@
  </PropertyGroup>
 
  <ItemGroup>
- <PackageReference Include="MediatR" Version="12.4.0"/>
+ <PackageReference Include="MediatR" Version="12.4.1"/>
  </ItemGroup>
 
  <ItemGroup>