[Spark][#36841] Add the DataSourceV2 unbounded source for the Spark 4 streaming runner - #39971

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: jwgmeligmeyling/checkstyle-github-action@v1. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/