update to v4 of actions/download-artifact

Author: DenisaCG

.github/workflows/build.yml

@@ -65,7 +65,7 @@ jobs:
       with:
         python-version: '3.9'
         architecture: 'x64'
-    - uses: actions/download-artifact@v3
+    - uses: actions/download-artifact@v4
       with:
         name: extension-artifacts
     - name: Install and Test
@@ -98,7 +98,7 @@ jobs:
       uses: jupyterlab/maintainer-tools/.github/actions/base-setup@v1
 
     - name: Download extension package
-      uses: actions/download-artifact@v3
+      uses: actions/download-artifact@v4
       with:
         name: extension-artifacts