chore(deps): update github artifact actions

Author: renovate[bot]

.github/workflows/build-preview.yml

@@ -27,7 +27,7 @@ jobs:
         run: pnpm build
 
       - name: Upload build artifact
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v5
         with:
           name: preview-build
           path: packages/svelte-ux/.svelte-kit

.github/workflows/deploy-preview.yml

@@ -18,7 +18,7 @@ jobs:
     if: ${{ github.event.workflow_run.conclusion == 'success' }}
     steps:
       - name: Download build artifact
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v6
         id: preview-build-artifact
         with:
           name: preview-build