use yarn if cache hit

.github/workflows/ci.yml

@@ -403,7 +403,7 @@ jobs:
       uses: cypress-io/github-action@v2
       with:
         working-directory: ./packages/app
-        install-command: npx lerna bootstrap -- --frozen-lockfile
+        install-command: ${{ (steps.cache-dependencies.outputs.cache-hit == 'true') && 'yarn') || 'npx' }} lerna bootstrap
         build: |
           cp config/ci/.env.local.for-ci .env.production.local
         start: yarn server