remove ambiguity of Setup/StartBundle javadocs in DoFn #19699
Description
@setup: "Annotation for the method to use to prepare an instance for processing bundles of elements."
@StartBundle: " Annotation for the method to use to prepare an instance for processing a batch of elements."
seems the same whereas first is initialization of the DoFn whereas second is initialization of the bundle.
Imported from Jira BEAM-7646. Original Jira may contain additional context.
Reported by: echauchot.