chore(deps): update github artifact actions

Author: renovate[bot]

.github/workflows/scheduler.yml

@@ -33,7 +33,7 @@ jobs:
           SPONSORKIT_MOONCELL_PATH: "./assets/data.csv"
 
       - name: Upload generated files
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v7
         with:
           name: generated
           path: |
@@ -53,7 +53,7 @@ jobs:
           ossutil-config: ${{ secrets.OSSUTIL_CONFIG }}
 
       - name: Download results
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v8
         with:
           name: generated
           path: ${{ github.workspace }}/generated