Update docs to reflect proper generic op output file usage

[akchinSTC]

What changes were proposed in this pull request?

Updated the docs and placeholder text in response to

#2789 and
#995 (comment)

How was this pull request tested?

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[ptitzler]

LGTM! Should we perhaps also reference the data volume topic as it provides an alternative for large (in terms of disk size or number of files) outputs ?

[akchinSTC]

LGTM! Should we perhaps also reference the data volume topic as it provides an alternative for large (in terms of disk size or number of files) outputs ?

Im probably going to follow that up in a separate PR since Id like to address the issues brought up by cupdike in #2794. Maybe updating the best practices doc and explain the diff between the intermediate volume workspace and the output file parameter

[cupdike]

Apologies if I am missing context here, but doesn't this suggest that wildcards actually are supported?
https://github.com/elyra-ai/elyra/blob/main/elyra/airflow/bootstrapper.py#L197

[akchinSTC]

thank you @cupdike.
@ptitzler, im probably going modify this PR a bit more while fixing #995, since the current documentation is correct (albeit with the bug). Listing files in outputs with wildcards does function correctly, but subsequent child nodes that we pass the wildcard path to cannot properly expand it and grab from s3.
wondering if we should disable wildcarding for now, so that subsequent nodes are able to proceed and provide guidance on how to properly push/pull artifacts to/from s3 (via compressed archives), or perhaps add the compression steps when wildcards are present to the bootstrapper and make the process transparent ?

[ptitzler]

Listing files in outputs with wildcards does function correctly, but subsequent child nodes that we pass the wildcard path to cannot properly expand it and grab from s3. wondering if we should disable wildcarding for now, so that subsequent nodes are able to proceed

In a way doing so would result in a breaking change, as there might be users that use this feature to make artifacts available in the last (or only) pipeline node.

and provide guidance on how to properly push/pull artifacts to/from s3 (via compressed archives), or perhaps add the compression steps when wildcards are present to the bootstrapper and make the process transparent ?

Should we perhaps we update the best practices document for now and fix the implementation (based on your suggestion) in a future release? We are at the tail end of the 3.10 release and I'm not sure the latter can be handled in time.