Bump Microsoft.DotNet.Arcade.Sdk

Bumps [Microsoft.DotNet.Arcade.Sdk](https://github.com/dotnet/arcade) from 8.0.0-beta.24360.6 to 8.0.0-beta.24421.4.
- [Commits](https://github.com/dotnet/arcade/commits)

---
updated-dependencies:
- dependency-name: Microsoft.DotNet.Arcade.Sdk
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

global.json

@@ -6,7 +6,7 @@
   "msbuild-sdks": {
     "Elskom.Sdk": "8.0.0",
     "Microsoft.Build.NoTargets": "3.7.56",
-    "Microsoft.DotNet.Arcade.Sdk": "8.0.0-beta.24360.6",
+    "Microsoft.DotNet.Arcade.Sdk": "8.0.0-beta.24421.4",
     "Microsoft.DotNet.SharedFramework.Sdk": "8.0.0-beta.24360.6"
   }
 }