Graceful shutdown trigger in case of err is broken

[alok87]

All routines are not getting shutdown and the main thread waits endlessly waiting for some to shutdown.

When this https://github.com/practo/tipoca-stream/blob/master/redshiftsink/pkg/redshiftbatcher/batch_processor.go#L505-L512 happens the processor sends error to the channel

the processor orchestrator gets this error and returns.

but the main is still waiting for some routines to shutdown.

Need to check and fix this.

[alok87]

This is happening because https://github.com/practo/tipoca-stream/blob/master/redshiftsink/pkg/serializer/message.go#L60 is getting stuck at the time of shutdown.

[alok87]

Solution discussion https://stackoverflow.com/questions/66707794/channels-and-graceful-shutdown-deadlock