make EventStreamTask non-throwing

nothing is awaiting the task so there's no pointer throwing an error, the best
we can do is return nil on the Flutter channel (which we do already)

This simplifies the code somewhat, we will ignore any errors and always remove
the task when the sequence completes or an error is thrown

Sources/FlutterSwift/Channel/FlutterEventChannel.swift

@@ -38,7 +38,7 @@ public final class FlutterEventChannel: _FlutterBinaryMessengerConnectionReprese
   public let codec: FlutterMessageCodec
   public let priority: TaskPriority?
 
-  private typealias EventStreamTask = Task<(), Error>
+  private typealias EventStreamTask = Task<Void, Never>
 
   private let _connection: ManagedAtomic<FlutterBinaryMessengerConnection>
   private let tasks: ManagedCriticalState<[String: EventStreamTask]>
@@ -163,14 +163,8 @@ public final class FlutterEventChannel: _FlutterBinaryMessengerConnectionReprese
     case "listen":
       let stream = try await onListen(call.arguments)
       let task = EventStreamTask(priority: priority) {
-        do {
-          try await self._run(for: stream, name: name)
-        } catch {
-          // at this point the task either ended normally or was cancelled;
-          // remove it from the task dictionary so that we don't leak tasks
-          self._removeTask(id)
-          throw error
-        }
+        try? await self._run(for: stream, name: name)
+        self._removeTask(id)
       }
       _addTask(id, task)
       envelope = FlutterEnvelope.success(nil)