Always download wasm opt from the binary (#4247)

* always download wasm opt from the binary

* clean up and pass clippy

* fix playwright commands

* don't cache dx target folder

.github/workflows/main.yml

@@ -221,6 +221,7 @@ jobs:
           npm ci
           npm install -D @playwright/test
           npx playwright install --with-deps
+          rm -rf ./target/dx
           npx playwright test
       - uses: actions/upload-artifact@v4
         if: always()