Update log level to debug from warning about scheduled_duration metric

[kzosabe]

closes: #34493

The previous PR (#34771) is stuck due to the complexity of the problem.
This incorrect warning is causing inconvenience to users, so we will make a change to stop it first.

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[gilt-cl]

@kzosabe Is there a chance this will be merged in the next release?

[kzosabe]

@gil-tober I hope it will, but I don't have the authority to decide that.
For some reason this PR and related issues have been forgotten by the maintainers of this OSS, so I am not sure if it will happen.

[gilt-cl]

@kaxil @XD-DENG @ashb
As @kzosabe mentioned, is there a chance for this to be merged in the upcoming release?

[potiuk]

Yes. It's very bad to keep you in a limbo like that especially after all the attempt you've made @kzosabe . Apologies for that in the name of all other maintainers. You seem to have a valid annoying issue that we generally avoided to handle.

I have no idea if it is right or wrong. This all seems from the implementation in #30612 and it seem to be somewhat broken anyway as indicated in #30612 (comment) and PR to likely fix some of that in #37936. Maybe @vandonr as the original author can chime in an comment on those. Seem that none of the other maintainers involved in the past discussions have picked up the discussion, but It's lkely better to avoid harm even if the discussion is not finished (cc: @hussein-awala @uranusjr).

I will ping them to see if they can be fixed in the original PRs, but for now I see no harm at all to change that warning into a debug mode. Happy to accept the change for 2.9.0, but:

a) please change it to debug.
b) please leave a comment explaining that this is temporary measure until the PR/issue is fixed.

Please ping me when it's done and I will merge it.

[kaxil]

Yup agreed with changing it to Debug in the meantime

[gilt-cl]

@potiuk @kaxil @Lee-W @kzosabe
Thanks for picking this up.
@HadarSha and I have been waiting for this for quite a long time.
We have about 1.3K DAG runs/70K tasks daily and this issue has prevented us from upgrading Airflow since 2.5.3

[potiuk]

Random failure. Merging.

[boring-cyborg]

Awesome work, congrats on your first merged pull request! You are invited to check our Issue Tracker for additional contributions.