Update README.md

[Hronom]

Fix getId() in example

Brief, plain english overview of your changes here

Fixes

Reminders

• Added/ran automated tests
• Update README and/or examples
• Ran mvn spotless:apply

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cc @kagkarlsson

[kagkarlsson]

Not sure if this was a bug? Isnt't .id referring to the field in MyTaskData?

[Hronom]

@kagkarlsson for a moment to me it appears as a wrong example, as attempt to print id of task. Maybe this is what confused e.g. we have id of task and we have extra id in MyTaskData