fix: Make dry_run optional per docs

[Calder-Ty]

This fixes#34563. It makes SetSingleTaskInstanceStateFormSchema load dry_run as False by default.
This matches what is declared in the api docs

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[hussein-awala]

IMHO it's a problem in the doc, dry_run should be True by default.

[hussein-awala]

Try to avoid unnecessary and unrelated changes

Suggested change

	session.query(TaskInstance).update(
	{TaskInstance.operator: None}, synchronize_session="fetch")
	session.query(TaskInstance).update({TaskInstance.operator: None}, synchronize_session="fetch")

[Calder-Ty]

Easy fix, will turn off my formatter

[hussein-awala]

Suggested change

	self.create_task_instances(session, task_instances=[
	{"state": State.REMOVED}], update_extras=True)
	self.create_task_instances(session, task_instances=[{"state": State.REMOVED}], update_extras=True)

[hussein-awala]

Suggested change

	count=session.query(TaskInstance).filter(
	count=session.query(TaskInstance).filter(TaskInstance.dag_id=="example_python_operator").count()

[Calder-Ty]

IMHO it's a problem in the doc, dry_run should be True by default.

I don't care about what the default is, however that change would technically be a breaking change. Albeit, no one can be depending on the declared functionality from the docs as it is broken.

[Calder-Ty]

I did not mean to close this. But will open a new PR.