Improve the readability of Operator.spawnTask(.)

[hXtreme]

The whole registering a Channel(Reader/Writer)Manager seems a bit messy. Try to abstract its logic away into the Channel Manager.

ScalingStream/src/main/java/org/example/scalingstream/dag/Operator.kt

Line 64 in 9de33ca

channelManager.registerChannelWriteManager(id, channelWriteManager)

ScalingStream/src/main/java/org/example/scalingstream/dag/Operator.kt

Line 91 in 9de33ca

channelManager.registerChannelReadManager(id, channelReadManager)