Fix: eslint warning in code example from the documentation: void is not valid as a constituent in a union type

[Josef-Friedrich]

eslint@typescript-eslint/no-invalid-void-type

Description

When I copy the example from the documentation into my project, these warnings appear:

void is not valid as a constituent in a union type eslint@typescript-eslint/no-invalid-void-type

Using undefined instead of void will fix this problem

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