[Flutter Error] The plugin tflite_flutter requires a higher Android SDK version.

위 에러는 해당 라이브러리를 사용하려면 Android SDK를 최소 21이상은 되어야한다는 말 입니다.

해결방법으로는 아래 코드처럼

/android/app/build.gradle에서 

적절한 minSdkVersion을 설정해줍니다.

   defaultConfig {
        // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
        applicationId "com.example.movenet"
        // You can update the following values to match your application needs.
        // For more information, see: https://docs.flutter.dev/deployment/android#reviewing-the-gradle-build-configuration.
        minSdkVersion 27
        // minSdkVersion flutter.minSdkVersion
        targetSdkVersion flutter.targetSdkVersion
        versionCode flutterVersionCode.toInteger()
        versionName flutterVersionName
    }