Fix link_names parameter not being passed to hook in SlackWebhookOperator

[kojiromike]

---

Only pass link_names if it has a non-Falsy value

Resolve #32917 by ensuring that SlackWebhookOperator only passes link_names to SlackWebhookHook if it has a non-Falsy value.

[boring-cyborg]

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[hussein-awala]

Please check STATIC_CODE_CHECKS doc to fix the failed test

[hussein-awala]

could you add a unit test to ensure that the argument is not provided when it's False?

[kojiromike]

I have been unable to get Breeze to build successfully so far. I'll keep trying, but it may take some time. If anyone wants to help, it would be appreciated.

[potiuk]

I have been unable to get Breeze to build successfully so far. I'll keep trying, but it may take some time. If anyone wants to help, it would be appreciated.

I wonder what errors you had ?

[Taragolis]

Suggested change

	# Unused Parameters, warn user if not None
	**({"link_names": self.link_names} if self.link_names else {}),

AFAIK I mark this value as not used for about I year, so we could just remove provide it in to the hook.

[Taragolis]

@kojiromike link_names completely removed in #33557, changelog and advice about migration to 8.0.0 https://airflow.apache.org/docs/apache-airflow-providers-slack/stable/changelog.html#breaking-changes