Skip unused Playwright setup in Gitea CI

.gitea/workflows/backend-quality-gate.yml

@@ -163,7 +163,6 @@ jobs:
       - name: Install dependencies
         env:
           PIP_INDEX_URL: https://mirrors.aliyun.com/pypi/simple/
-          PLAYWRIGHT_DOWNLOAD_HOST: https://registry.npmmirror.com/-/binary/playwright
           NPM_CONFIG_REGISTRY: https://registry.npmmirror.com
         run: |
           set -euo pipefail
@@ -176,8 +175,7 @@ jobs:
             "numpy==2.5.1" \
             "pandas==2.3.3" \
             "timezonefinder==8.2.5" \
-            -r requirements.txt -r requirements-dev.txt playwright
-          python -m playwright install --with-deps chromium
+            -r requirements.txt -r requirements-dev.txt
           npm ci --prefix frontend
 
       - name: Validate backend, package, frontend, and database contracts