问Android: Gradle build一直在使用最新的NDK版本，而不是使用已经安装的版本。

EN

Welcome to Gradle 5.1.1!

Here are the highlights of this release:
 - Control which dependencies can be retrieved from which repositories
 - Production-ready configuration avoidance APIs

For more details see https://docs.gradle.org/5.1.1/release-notes.html

Starting a Gradle Daemon (subsequent builds will be faster)

> Configure project :ui_manager_library
Checking the license for package NDK in /usr/local/android-sdk/licenses
License for package NDK accepted.
Preparing "Install NDK (revision: 22.0.7026061)".
"Install NDK (revision: 22.0.7026061)" ready.
Installing NDK in /usr/local/android-sdk/ndk-bundle
"Install NDK (revision: 22.0.7026061)" complete.
"Install NDK (revision: 22.0.7026061)" finished.
NDK is missing a "platforms" directory.
If you are using NDK, verify the ndk.dir is set to a valid NDK directory.  It is currently set to /usr/local/android-sdk/ndk-bundle.
If you are not using NDK, unset the NDK variable from ANDROID_NDK_HOME or local.properties to remove this warning.


FAILURE: Build failed with an exception.

ANDROID_NDK_HOME='/usr/local/android-sdk/ndk/20.0.5594570'

android {
    ndkVersion '20.0.5594570'
}