GitHub Actions now allows developers to use environments without auto-deployment [GA]

### Value Prop

GitHub Environments auto-deploy when added to Actions workflows. This is useful, but also a pain point if you only want to use the environment's variables, not deploy to it. Using environments to store secrets and bind them to a branch is a huge security win, but for others it's more about usability and avoiding deployment spam on a pull request.[/+]

### Expected Outcome

With this release, developers can now use environments without them auto-deploying them. This will be accomplished by adding a boolean option in Actions workflows to note if deployment is true or false.

未指定任何实现文件或测试。首先查看 issue 中描述的 GitHub Actions 环境行为，并确定 workflow 的环境配置定义在哪里；当 workflow 可以使用某个环境的变量而不触发该环境的 deployment 时，工作即完成。

由索引模型根据 Issue 内容生成。