compileSdkVersion is not specified error

While building the project in 101 the following error appears...

FAILURE: Build failed with an exception.

Where: Build file '/Users/mcativa/Documents/GitHub/Material Design/material-components-flutter-codelabs/mdc_100_series/android/build.gradle' line: 26
What went wrong: A problem occurred evaluating root project 'android'.

A problem occurred configuring project ':app'. compileSdkVersion is not specified.
While the problems ir reported in ./android/build.gradle' it should be fixed in ./android/app/build.gradle next to:
```
targetSdkVersion 28
//Add following
compileSdkVersion 28
```

material-components / material-components-flutter-codelabs