Update srtool.yml (#1720)

Author: adamdossa

.github/workflows/srtool.yml

@@ -34,7 +34,7 @@ jobs:
           echo - prop: ${{ steps.srtool_build.outputs.proposal_hash }}
           echo "Runtime location: ${{ steps.srtool_build.outputs.wasm }}"
       - name: Archive Runtime
-        uses: actions/upload-artifact@v2
+        uses: actions/upload-artifact@v4
         with:
           name: ${{ matrix.chain }}-runtime-${{ github.sha }}
           path: |