smoke3: go download via CN mirror

.gitea/workflows/smoke3.yml

@@ -0,0 +1,20 @@
+name: smoke3
+on: [push]
+jobs:
+  tools:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-go@v5
+        with:
+          go-version: "1.25.x"
+          go-download-base-url: "https://golang.google.cn/dl"
+      - name: go check
+        run: |
+          go version
+          go env GOROOT
+      - name: npm check
+        run: |
+          npm --version
+          npm config get registry
+          timeout 240 npx --yes cowsay@1.6.0 "npm-ok" || echo "NPM_FAILED"