Fix Galata bot

Author: martinRenou

.github/workflows/update_galata_references.yml

@@ -47,15 +47,16 @@ jobs:
       - name: Install JS deps
         run: |
           jlpm
-          jlpm playwright install chromium
           jlpm build
         working-directory: js
 
       - name: Install labextension
         run: jupyter labextension develop . --overwrite
 
       - name: Install ui-tests
-        run: jlpm install --frozen-lockfile
+        run: |
+          jlpm install --frozen-lockfile
+          jlpm playwright install chromium
         working-directory: ui-tests
 
       - uses: jupyterlab/maintainer-tools/.github/actions/update-snapshots@main