Mark Multiple Executor Configuration as stable in Airflow 3

[o-nikolas]

Multiple Executor Configuration (aka hybrid executors, AIP-61) has been released for over half a year and it will be almost a year when Airflow 3.0 is released. I think with the release of Airflow 3 we can call it stable, but keep in as experimental in 2.10.X and 2.11.X in case any issues are discovered during those releases.

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[o-nikolas]

Optionally we could mark it as stable in 2.11 if we wanted to give people more time to migrate. Thoughts?

[eladkal]

I think we better have lazy consensus vote on this one.
Also we need to decide what to do with CeleryKubernetesExecutor and the others od that kind. They qere not deprecated because Hybrid was marked experimintal.

Personally I would prefer to wait with marking it stable. There were reports on this feature not working with helm chart and so far the fix was not released (waiting for chart 1.16)

[o-nikolas]

I think we better have lazy consensus vote on this one. Also we need to decide what to do with CeleryKubernetesExecutor and the others od that kind. They qere not deprecated because Hybrid was marked experimintal.

Personally I would prefer to wait with marking it stable. There were reports on this feature not working with helm chart and so far the fix was not released (waiting for chart 1.16)

I agree, I was just typing up a discussion thread for this actually! I will send that out.

I think a course of action that's in the middle is mark this as stable in 2.11 and very publicly mark the old hard coded executors as deprecated in 2.11 and then. Remove them in 3.0

I don't personally think issues with the helm chart stop multi exec config from being stable. That is not related to bugs in the fundamental interface of that feature.

[potiuk]

I don't personally think issues with the helm chart stop multi exec config from being stable. That is not related to bugs in the fundamental interface of that feature.

As explained in the devlist message. While it's not a blocker, a call to make it works should be included in a call to make the feature stable.

[o-nikolas]

Now that #46944 is merged, and Jed is planning to release a new Helm Chart soon, we should be able to merge this one as well.

This small PR simply maintains consistency with the above mentioned change in 2.10.X

CC: @jedcunningham @jscheffl @amoghrajesh

[amoghrajesh]

Late approval but looks good!