问题描述：Failed to install the following Android SDK packages as some licences have not been accepted.

第一次执行react-native run-android报错：

Failed to install the following Android SDK packages as some licences have not been accepted.
build-tools;29.0.2 Android SDK Build-Tools 29.0.2
platforms;android-29 Android SDK Platform 29

info Installing the app...
Starting a Gradle Daemon, 1 incompatible and 1 stopped Daemons could not be reused, 
use --status for details
Checking the license for package Android SDK Build-Tools 29.0.2 in C:\Android\licenses
Warning: License for package Android SDK Build-Tools 29.0.2 not accepted.
Checking the license for package Android SDK Platform 29 in C:\Android\licenses
Warning: License for package Android SDK Platform 29 not accepted.

FAILURE: Build failed with an exception.

* What went wrong:
Could not determine the dependencies of task ':app:installDebug'.
> Failed to install the following Android SDK packages as some licences have not been
> accepted.
     build-tools;29.0.2 Android SDK Build-Tools 29.0.2
     platforms;android-29 Android SDK Platform 29
  To build this project, accept the SDK license agreements and install the missing 
  components using the Android Studio SDK Manager.
  Alternatively, to transfer the license agreements from one workstation to another, 
  see http://d.android.com/r/studio-ui/export-licenses.html

  Using Android SDK: C:\Android

* 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 14s

error Failed to install the app. Please accept all necessary Android SDK licenses using 
Android SDK Manager: "$ANDROID_HOME/tools/bin/sdkmanager --licenses".
Error: Command failed: gradlew.bat app:installDebug -PreactNativeDevServerPort=8081