Added documentation for return vs yield usage in DoFn.process()

[YashaswiniTB]

Issue Link : #34906
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[github-actions]

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[damccorm]

Thanks for picking this up!

[YashaswiniTB]

@damccorm kindly review the PR and approve it

[damccorm]

Please also check the precommits which are automatically run. In this case, the whitespace precommit is failing because you have trailing whitespace in some of your lines

[damccorm]

Could you please flip the order of the descriptions and the examples? Otherwise, I worry people will just read the example and follow it without seeing the description saying it is wrong

[damccorm]

It does not look like you addressed this - please move the "Returning a single element" section to the back of the order

[github-actions]

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[damccorm]

waiting on author

[YashaswiniTB]

waiting on author

Thanks @damccorm! I believe I’ve addressed all the comments. Please let me know if anything else is required

[derrickaw]

waiting on author

[damccorm]

Thanks - this lgtm other than 2 changes which I'll apply before merging