Update upgrading.rst with detailed code example of how to resolve post-upgrade warning

[adaezebestow]

Give a detailed code example for how to drop the _airflow_moved__2_2__task_instance table to resolve post-upgrade warning

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In case of fundamental code change, Airflow Improvement Proposal (AIP) is needed.
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In case of backwards incompatible changes please leave a note in UPDATING.md.

[boring-cyborg]

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[github-actions]

The PR is likely ready to be merged. No tests are needed as no important environment files, nor python files were modified by it. However, committers might decide that full test matrix is needed and add the 'full tests needed' label. Then you should rebase it to the latest main or amend the last commit of the PR, and push it with --force-with-lease.

[potiuk]

Nice! I really like when we give "good" guidance to our users.

[potiuk]

Some whitespace problem :(

[potiuk]

I think there is an empty line problem

[uranusjr]

The command example here is out of place since it is specific to Kubernetes, while the rest of the document does not make the assumption, and already assumes you have hooked into the machine/container/pod/whatever. I would only add the second bullet point.

[potiuk]

I'd rather give some more examples - kubernetes, docker, docker-compose and tell the users that this is an example and that they should find out what they should do in their environment.

I think our assumption is that this documentation is used by the users who had never done low-level DB operations with Airflow DB, and they likely have no idea how to get to their containers. Giving them at least a handy example they could follow and at least the starting point that will allow them to ask the right google question to dig deeper is useful.

[eladkal]

I think this is just need to be in a note block that mention this is K8s specific

[potiuk]

Absolutely

[adaezebestow]

The note block makes sense

[potiuk]

Can we get update on that one :) @adaezebestow ?

[adaezebestow]

Hey @potiuk, I made an update specifying that the code suggestion is specific to Kubernetes. I tried unsuccessfully to reformat it into a note block.

[potiuk]

Docs are failing - I think you need ot look at similar .rst files :)

something like .. note:: should do the trick

[eladkal]

probably it's just missing a blank line.
I submitted a fix it should make the CI happy

[potiuk]

Ci Indeed looks happy :)

[boring-cyborg]

Awesome work, congrats on your first merged pull request!