fix: (DeclarativeOAuthFlow) - make the extract_output Optional; correct the descriptions

[bazarnov]

What

Resolving:

• https://github.com/airbytehq/airbyte-internal-issues/issues/11422

After this change: https://github.com/airbytehq/airbyte-platform-internal/pull/15040, there is no need to have the extract_output as the required field to be provided, we will leverage the complete_oauth_output_specification.path_in_oauth_response instead.

User Impact

No impact is expected. This is not a breaking change.

[bazarnov]

@bnchrch This CI check is red, for an unknown reason to me: https://github.com/airbytehq/airbyte-protocol/actions/runs/12892021428/job/35945312729?pr=106

I've also tested on a clean main branch, here is the TEST ON MAIN PR, it fails the same way, which is worth tackling, I believe.

Who is responsible for maintaining this repo and the related processes?

[bazarnov]

Running the protocol-models/bin/generate-python-pydantic-v2-docker.sh locally fails with the same way for the main branch.

[bnchrch]

@bazarnov I believe I have a fix here. Will merge once tests pass.

[bazarnov]

@bazarnov I believe I have a fix here. Will merge once tests pass.

If you can provide the details, it'd be helpful for future reference. Thanks.

[bnchrch]

@bazarnov merged here #108