[#620] Add support for optional attach parameter to disable artifact attachment

[peter277]

Add support for optional attach parameter to disable artifact attachment

fixes #620

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[peter277]

simple test will be appreciated

I have added a new integration test attach_skip to this pull request to test the new parameter's behaviour. Would appreciate your review.

[peter277]

Hi Team - just checking in to see if there’s anything I can do to help move this PR forward? Happy to make adjustments if needed.

CC: @slawekjaranowski, @bmarwell

[peter277]

Thanks @bmarwell for the review - I have incorporated your suggested changes into the branch.

[peter277]

Hi Team - just checking in to see if there’s anything else needed before this PR can be merged? Do I need to sign an individual contributor license agreement, given that the change only adds a flag?

Was hoping there might be a release in the near future including this change so that I could start using it.