fix(adapter-pg): serialize queries within a transaction - #29468

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: andresz1/size-limit-action@v1, pnpm/action-setup@v4.2.0. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/