Tweak strict_dataset_uri_validation documentation wording

[uranusjr]

See #43915. The warning message also already says this will be a hard error in Airflow 3.

airflow/airflow/datasets/__init__.py

Lines 114 to 119 in 0380160

	warnings.warn(
	f"The dataset URI {uri} is not AIP-60 compliant: {exception}. "
	f"In Airflow 3, this will raise an exception.",
	UserWarning,
	stacklevel=3,
	)