Revert "maintainer: mainter manager use parallel DS (pingcap#706)"

This reverts commit cf291d1.

.github/workflows/uint_test.yaml

@@ -88,4 +88,5 @@ jobs:
       - name: Unit Test
         run: |
           go test --tags=intest -timeout 120s  github.com/pingcap/ticdc/coordinator/...
+          go test --tags=intest -timeout 120s  github.com/pingcap/ticdc/pkg/eventservice...
 

maintainer/maintainer_manager.go

@@ -82,7 +82,7 @@ func NewMaintainerManager(selfNode *node.Info,
 		tsoClient:     pdClient,
 		regionCache:   regionCache,
 	}
-	m.stream = dynstream.NewParallelDynamicStream(func(path common.GID) uint64 { return path.FastHash() }, NewStreamHandler())
+	m.stream = dynstream.NewDynamicStream(NewStreamHandler())
 	m.stream.Start()
 
 	mc.RegisterHandler(messaging.MaintainerManagerTopic, m.recvMessages)

utils/dynstream/interfaces.go

@@ -249,17 +249,15 @@ func (f *Feedback[A, P, D]) String() string {
 	return fmt.Sprintf("DynamicStream Feedback{Area: %v, Path: %v, Pause: %v}", f.Area, f.Path, f.Pause)
 }
 
-// NewDynamicStream creates a new dynamic stream with a single stream by default.
 func NewDynamicStream[A Area, P Path, T Event, D Dest, H Handler[A, P, T, D]](handler H, option ...Option) DynamicStream[A, P, T, D, H] {
 	opt := NewOption()
-	opt.StreamCount = 1
 	if len(option) > 0 {
 		opt = option[0]
 	}
+	opt.StreamCount = 1
 	return newParallelDynamicStream(func(path P) uint64 { return 0 }, handler, opt)
 }
 
-// NewParallelDynamicStream creates a new dynamic stream with CPU number streams by default.
 func NewParallelDynamicStream[A Area, P Path, T Event, D Dest, H Handler[A, P, T, D]](hasher PathHasher[P], handler H, option ...Option) DynamicStream[A, P, T, D, H] {
 	opt := NewOption()
 	if len(option) > 0 {