Add a ProGuard rule to ignore warnings from the BouncyCastle library.

Author: oliexdev

android_app/app/proguard-rules.pro

@@ -56,4 +56,7 @@
 # Keep all classes that extend CoroutineWorker and BroadcastReceiver
 # The standard rules from AndroidManifest usually handle this, but being explicit is safer.
 -keep class * extends androidx.work.CoroutineWorker
--keep class * extends android.content.BroadcastReceiver
+-keep class * extends android.content.BroadcastReceiver
+
+# BouncyCastle
+-dontwarn org.bouncycastle.**