修复Android ci编译问题

Android/app/build.gradle

@@ -2,6 +2,7 @@ apply plugin: 'com.android.application'
 
 
 android {
 android {
     compileSdkVersion 28
     compileSdkVersion 28
+    ndkVersion "21.4.7075529"
     defaultConfig {
     defaultConfig {
         applicationId "com.zlmediakit.demo"
         applicationId "com.zlmediakit.demo"
         minSdkVersion 15
         minSdkVersion 15