Fix individual group subs

libsignal/src/main/java/org/session/libsignal/utilities/PromiseUtilities.kt

@@ -3,6 +3,7 @@ package org.session.libsignal.utilities
 
 import nl.komponents.kovenant.Promise
 import nl.komponents.kovenant.deferred
+import nl.komponents.kovenant.functional.map
 import nl.komponents.kovenant.task
 import java.util.concurrent.TimeoutException
 
@@ -58,4 +59,11 @@ fun <V> Promise<V, Exception>.timeout(millis: Long): Promise<V, Exception> {
         if (!deferred.promise.isDone()) { deferred.reject(it) }
     }
     return deferred.promise
-}
+}
+
+infix fun <V, E: Exception> Promise<V, E>.sideEffect(
+    callback: (value: V) -> Unit
+) = map {
+    callback(it)
+    it
+}