test(e2e): missing pnpm install on sso extension

Signed-off-by: Daniel Villanueva <[email protected]>

.github/workflows/pr-check.yaml

@@ -157,10 +157,14 @@ jobs:
           run_install: false
           package_json_file: ./podman-desktop/package.json
 
-      - name: Execute pnpm
+      - name: Install Podman Desktop dependencies
         working-directory: ./podman-desktop
         run: pnpm install
 
+      - name: Install SSO extension dependencies
+        working-directory: ./sso-extension
+        run: pnpm install
+
       - name: Build Podman Desktop for E2E tests
         working-directory: ./podman-desktop
         run: pnpm test:e2e:build