[CI] Bump actions/upload-artifact from 4 to 5

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] <[email protected]>

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -133,7 +133,7 @@ jobs:
     # allows us to diff the expected and actual golden file contents.
     - name: 📦 Upload golden files
       if: ${{ steps.test.outcome != 'success' && always() }}
-      uses: actions/upload-artifact@v4
+      uses: actions/upload-artifact@v5
       with:
         name: golden-files-${{ runner.os }}-ghc-${{ steps.setup-haskell.outputs.ghc-version }}-cabal-${{ steps.setup-haskell.outputs.cabal-version }}-plan-${{ hashFiles('dist-newstyle/cache/plan.json') }}
         path: lsm-tree/test/golden-file-data

.github/workflows/documentation.yml

@@ -84,7 +84,7 @@ jobs:
       run: ./scripts/generate-haddock.sh
 
     - name: 📦 Upload documentation
-      uses: actions/upload-artifact@v4
+      uses: actions/upload-artifact@v5
       with:
         name: haddocks-${{ runner.os }}-ghc-${{ env.ghc-version }}-cabal-${{ env.cabal-version }}
         path: haddocks