samples/compat project doesn't run: "The serve command requires to be run in an Angular project, but a project definition could not be found."

### Version info

**Angular:**
13.3.0

**Firebase:**
10.1.4

**AngularFire:**
How do you find your AngularFire version?

**Other (e.g. Ionic/Cordova, Node, browser, operating system):**

### How to reproduce these conditions

Forked and cloned the latest version from

https://github.com/angular/angularfire/tree/master/samples/compat

Ran 'ng serve' and got an error:

`The serve command requires to be run in an Angular project, but a project definition could not be found.`

### Expected behavior

Sample code should run.

### Actual behavior

Sample code doesn't run.

从 samples/compat 项目开始，在克隆的 sample 中运行 `ng serve`，以复现缺少项目定义的错误。检查 Angular 项目配置以及相关的 workspace 入口点；当 compat sample 能够通过 `ng serve` 成功启动时即表示完成。

由索引模型根据 Issue 内容生成。