build(deps): bump actions/upload-artifact from 3 to 4

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

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

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

.github/workflows/dotnet.yml

@@ -41,7 +41,7 @@ jobs:
     - name: Test
       run: dotnet test --no-build --verbosity normal
     - name: Upload Artifacts
-      uses: actions/upload-artifact@v3
+      uses: actions/upload-artifact@v4
       with:
         name: plugin
         path: |
@@ -66,7 +66,7 @@ jobs:
           cp -r ./unity/AssetBundles/StandaloneWindows/* ./artifact/BepInEx/plugins/techtonica_vr/assets
           cp {README.adoc,CHANGELOG.md,LICENSE,manifest.json,icon.png} ./artifact/
       - name: Upload Release Asset Artifact
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: release-artifact
           path: artifact