example: add callback examples #425

Job	Run time
setup	5s
Hello World	57s
Basic Step	53s
Step with Retry	1m 5s
Step with Name	1m 3s
Wait State	53s
Wait for Callback Success	1m 1s
Multiple Wait	53s
Callback	1m 1s
Wait for Callback Failure	1m 0s
Wait For Callback Heartbeat Sends	59s
Wait For Callback Multiple Invocations	56s
Wait For Callback With Child Context	1m 17s
Wait For Callback Submitter Failure	1m 18s
Wait For Callback Mixed Ops	1m 9s
Wait For Callback Success Anonymous	55s
Wait For Callback Serdes	1m 1s
Wait For Callback Nested	1m 3s
Wait For Callback Failing Submitter Catchable	1m 3s
Parallel Operations	51s
Wait for Condition	1m 10s
Steps with Retry	56s
Map Large Scale	59s
Parallel with Max Concurrency	1m 7s
Run in Child Context Large Data	56s
Map Operations	51s
Logger Example	1m 1s
Run in Child Context	55s
Parallel with Wait	55s
Block Example	1m 15s
Simple Execution	59s
Map with Min Successful	1m 4s
Parallel with Batch SerDes	1m 0s
Map with Custom SerDes	53s
Parallel with Failure Tolerance	56s
Map with Batch SerDes	57s
Parallel with Custom SerDes	58s
Map with Failure Tolerance	55s
Create Callback Mixed Operations	57s
None Results	1m 5s
Create Callback Heartbeat	58s
Handler Error	1m 8s
Callback Success	1m 5s
Create Callback Custom Serdes	56s
Callback Success None	55s
Map with Max Concurrency	1m 0s
	45m 14s

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