github-actions(deps): bump actions/setup-dotnet from 4 to 5

Bumps [actions/setup-dotnet](https://github.com/actions/setup-dotnet) from 4 to 5.
- [Release notes](https://github.com/actions/setup-dotnet/releases)
- [Commits](actions/setup-dotnet@v4...v5)

---
updated-dependencies:
- dependency-name: actions/setup-dotnet
  dependency-version: '5'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/RocketModFix.UnityEngine.Redist.yaml

@@ -12,7 +12,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v5
-    - uses: actions/setup-dotnet@v4
+    - uses: actions/setup-dotnet@v5
       name: Setup .NET
       with:
         dotnet-version: 8.x