Add production Greenlight credentials example

snippets/kotlin_mpp_lib/shared/src/commonMain/kotlin/com/example/kotlinmpplib/Production.kt

@@ -0,0 +1,16 @@
+package com.example.kotlinmpplib
+
+import breez_sdk.*
+class Production {
+    fun productionNodeConfig(): NodeConfig {
+        // ANCHOR: moving-to-production
+        // Read your Greenlight credentials from secure storage
+        val deviceKey = emptyList<UByte>()
+        val deviceCert = emptyList<UByte>()
+        val greenlightCredentials = GreenlightCredentials(deviceKey, deviceCert)
+
+        val nodeConfig = NodeConfig.Greenlight(GreenlightNodeConfig(greenlightCredentials, null))
+        // ANCHOR_END: moving-to-production
+        return nodeConfig
+    }
+}