Allow disabling activation offloading streams in full finetune recipe

[nathan-az]

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#2683

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What are the changes made in this PR?

• Allows configuring use_streams in activation offloading

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[nathan-az]

@joecummings @janeyx99 @ebsmothers Let me know if this looks like a reasonable stopgap. I'm not certain that it completely solves the issue (also curious if anyone can repro both the instability, and that this change fixes it). I assume that if the issue is the streams, fixing it properly may be quite a bit higher effort.

[janeyx99]

@nathan-az I think allowing a nonstreams option is good! Your inclination is right that if it is streams that’s the problem, it will be nontrivial to fix.

[ebsmothers]

@nathan-az thanks for opening this! I agree, this looks like a reasonable fix to unblock TP with activation offloading