🔧 [Android] Declare WRITE_EXTERNAL_STORAGE with SDK constraint

Author: AlexV525

example/android/app/src/main/AndroidManifest.xml

@@ -2,7 +2,9 @@
     package="com.fluttercandies.wechatAssetsPickerExample">
 
     <uses-permission android:name="android.permission.INTERNET" />
-    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
+    <uses-permission
+        android:name="android.permission.WRITE_EXTERNAL_STORAGE"
+        android:maxSdkVersion="29"/>
 
     <application
         android:label="Wechat Assets Picker Example"