fix(providers/common/sql): add dummy connection setter for backward compatibility

[Lee-W]

Why

The introduction of connection property breaks apache-airflow-providers-mysql<5.7.1, apache-airflow-providers-elasticsearch<5.5.1 and apache-airflow-providers-postgres<5.13.0

What

Add a dummy connection setter

Closes: #42452

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[ashb]

This stops the error, but why does it work? Were those providers never reading self.connection again?

[Lee-W]

This stops the error, but why does it work? Were those providers never reading self.connection again?

They're reading through the newly introduced property connection (since common-sql > 1.17.0)

[ephraimbuddy]

Can you patch this change on old common/sql and test with the affected mysql?

My understanding is that the connection would be read from 'get_conn' which validates this change but yeah, let's test with a patch

[dabla]

Does the dummy setter solve this issue now? The problem is caused by my PR 40751.

[Lee-W]

Can you patch this change on old common/sql and test with the affected mysql?

My understanding is that the connection would be read from 'get_conn' which validates this change but yeah, let's test with a patch

Yep, works as expected

[dabla]

Can you patch this change on old common/sql and test with the affected mysql?
My understanding is that the connection would be read from 'get_conn' which validates this change but yeah, let's test with a patch

Yep, works as expected

Good to hear, sorry for the caused inconvenience.