fix: ConsumerFilterRegistry unique actor name (#1192)

akka-projection-grpc/src/main/scala/akka/projection/grpc/internal/ConsumerFilterRegistry.scala

@@ -7,11 +7,13 @@ package akka.projection.grpc.internal
 import scala.concurrent.duration._
 import java.net.URLEncoder
 import java.nio.charset.StandardCharsets
+import java.util.UUID
 
 import scala.collection.immutable
 import scala.util.Failure
 import scala.util.Success
 
+import akka.actor.InvalidActorNameException
 import akka.actor.typed.ActorRef
 import akka.actor.typed.Behavior
 import akka.actor.typed.scaladsl.ActorContext
@@ -61,9 +63,17 @@ import akka.util.Timeout
       stores.get(streamId) match {
         case Some(store) => store
         case None =>
-          context.spawn(
-            ConsumerFilterStore(context.system, settings, streamId, context.self),
-            URLEncoder.encode(streamId, StandardCharsets.UTF_8.name))
+          val encodedStreamId = URLEncoder.encode(streamId, StandardCharsets.UTF_8.name)
+          try {
+            context.spawn(ConsumerFilterStore(context.system, settings, streamId, context.self), encodedStreamId)
+          } catch {
+            case _: InvalidActorNameException =>
+              // There could be a race condition from SubscriberTerminated where the child is stopped,
+              // but not removed yet. The actor name isn't important, but could be useful for debugging.
+              context.spawn(
+                ConsumerFilterStore(context.system, settings, streamId, context.self),
+                s"$encodedStreamId-${UUID.randomUUID()}")
+          }
       }
     }