Bump actions/upload-artifact from 4 to 5 (#916)

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

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

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

Author: dependabot[bot]

.github/workflows/release_documentation.yml

@@ -24,7 +24,7 @@ jobs:
         working-directory: ./docs
 
       - name: Upload documentation
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v5
         with:
           name: docs
           path: |

.github/workflows/release_packages.yml

@@ -18,7 +18,7 @@ jobs:
         run: dotnet pack src/NSubstitute/NSubstitute.csproj -o bin -p:CI=true
 
       - name: Upload packages
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v5
         with:
           name: packages
           path: |