ci: simplify workflow

Author: bitsnaps

.github/workflows/npm-build.yml

@@ -17,5 +17,5 @@ jobs:
       - uses: actions/setup-node@v4
         with:
           node-version: ${{ matrix.node-version }}
-      - run: npm ci
-      - run: npm test
+      - run: pnpm install --frozen-lockfile
+      - run: pnpm test