snapshot(ticdc): fix ddl puller and ddl manager stuck caused by two dead lock (#11886)

close #11884

Author: wlwilliamx

cdc/entry/schema/snapshot.go

@@ -570,9 +570,6 @@ func (s *Snapshot) SchemaCount() (count int) {
 
 // DumpToString dumps the snapshot to a string.
 func (s *Snapshot) DumpToString() string {
-	s.rwlock.RLock()
-	defer s.rwlock.RUnlock()
-
 	schemas := make([]string, 0, s.inner.schemas.Len())
 	s.IterSchemas(func(dbInfo *timodel.DBInfo) {
 		schemas = append(schemas, fmt.Sprintf("%v", dbInfo))

cdc/entry/schema_storage.go

@@ -273,8 +273,7 @@ func (s *schemaStorage) AllPhysicalTables(ctx context.Context, ts model.Ts) ([]m
 	log.Debug("get new schema snapshot",
 		zap.Uint64("ts", ts),
 		zap.Uint64("snapTs", snap.CurrentTs()),
-		zap.Any("tables", res),
-		zap.String("snapshot", snap.DumpToString()))
+		zap.Any("tables", res))
 
 	return res, nil
 }