add missing step to rust in android docs

docs/src/getting-started/rust-in-android.md

@@ -149,3 +149,16 @@ class MainActivity : AppCompatActivity() {
     }
 }
 ```
+
+Add the following to your build.gradle file to link the library:
+
+```kotlin
+sourceSets {
+       named("main") {
+           jniLibs.srcDir("src/main/jni/")
+           // Configure the JNI libraries directory
+           // Note: For newer configurations, JNI libraries are often managed differently
+           // Check your specific plugin version's documentation for precise configuration
+       }
+   }
+```

light_client_app/android/app/src/main/java/com/example/beerus_android/Beerus.java

@@ -0,0 +1,4 @@
+package com.example.beerus_android;
+
+public class Beerus {
+}