Bump actions/setup-dotnet from 5 to 6

Bumps [actions/setup-dotnet](https://github.com/actions/setup-dotnet) from 5 to 6.
- [Release notes](https://github.com/actions/setup-dotnet/releases)
- [Commits](https://github.com/actions/setup-dotnet/compare/v5...v6)

---
updated-dependencies:
- dependency-name: actions/setup-dotnet
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

.github/workflows/build.yaml

@@ -152,7 +152,7 @@ jobs:
 
       - name: Setup .NET for Velopack
         if: (runner.os == 'Windows' || runner.os == 'macOS') && (github.event.inputs.installer_type || 'velopack') == 'velopack'
-        uses: actions/setup-dotnet@v5
+        uses: actions/setup-dotnet@v6
         with:
           dotnet-version: '9.0.x'