Add LibTest getTestDataDir to fix sled test on android

bdk-kotlin/android/src/androidTest/java/org/bitcoindevkit/bdk/AndroidLibTest.kt

@@ -1,11 +1,11 @@
 package org.bitcoindevkit.bdk
 
+import android.app.Application
+import android.content.Context.MODE_PRIVATE
+import androidx.test.core.app.ApplicationProvider
 import androidx.test.ext.junit.runners.AndroidJUnit4
-
 import org.junit.runner.RunWith
 
-import org.junit.Assert.*
-
 /**
  * Instrumented test, which will execute on an Android device.
  *
@@ -13,5 +13,9 @@ import org.junit.Assert.*
  */
 @RunWith(AndroidJUnit4::class)
 class AndroidLibTest : LibTest() {
+    override fun getTestDataDir(): String {
+        val context = ApplicationProvider.getApplicationContext<Application>()
+        return context.getDir("bdk-test", MODE_PRIVATE).toString()
+    }
 
 }

bdk-kotlin/android/src/main/AndroidManifest.xml

@@ -1,5 +1,5 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
-    package="org.bitcoindevkit.bdk" >
+    package="org.bitcoindevkit.bdk">
 
     <uses-permission android:name="android.permission.INTERNET" />