Error RUN

Hi, i need help. When i was running the starter app, after add google json and sync files, i got error this:
```
======
Executing tasks: [:build-android-start:app:assembleDebug] in project C:\Users\USER-HP\AndroidStudioProjects\codelab-friendlychat-android

Configuration on demand is an incubating feature.

FAILURE: Build completed with 2 failures.

1: Task failed with an exception.
-----------
* Where:
Build file 'C:\Users\USER-HP\AndroidStudioProjects\codelab-friendlychat-android\build-android-start\app\build.gradle' line: 2

* What went wrong:
A problem occurred evaluating project ':build-android-start:app'.
> Plugin with id 'com.google.firebase.crashlytics' not found.

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.
==============================================================================

2: Task failed with an exception.
-----------
* What went wrong:
A problem occurred configuring project ':build-android-start:app'.
> compileSdkVersion is not specified. Please add it to build.gradle

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.
==============================================================================

* Get more help at https://help.gradle.org

BUILD FAILED in 311ms
```