Bump actions/setup-dotnet from 3 to 4 (#318)

Bumps [actions/setup-dotnet](https://github.com/actions/setup-dotnet) from 3 to 4.
- [Release notes](https://github.com/actions/setup-dotnet/releases)
- [Commits](actions/setup-dotnet@v3...v4)

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

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

Author: dependabot[bot]

.github/workflows/samples-dotnet.yaml

@@ -27,7 +27,7 @@ jobs:
           - samples/server/petstore/aspnetcore-6.0-project4Models
     steps:
       - uses: actions/checkout@v4
-      - uses: actions/setup-dotnet@v3
+      - uses: actions/setup-dotnet@v4
         with:
           dotnet-version: '6.0.x'
       - name: Build