Fix Amazon system tests creating connections on Airflow 2

[vincbeck]

These Dags created their Airflow connection through the REST API, which only exists in Airflow 3, so on Airflow 2 the setup task kept retrying against a non-existent API server until it failed. The shared test helper already knows how to create a connection on both versions.

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[seanghaeli]

Looks good, just noticed this pattern is also present in example_google_api_youtube_to_s3:

airflow/providers/amazon/tests/system/amazon/aws/example_google_api_youtube_to_s3.py

Lines 99 to 107 in b5547c4

	make_authenticated_rest_api_request(
	path="/api/v2/connections",
	method="POST",
	body={
	"connection_id": conn_id_name,
	"conn_type": "google_cloud_platform",
	"extra": json.dumps(conn_extra),
	},
	)

I know we don't run this test on our dashboard but it might be good to get rid of the pattern entirely from the codebase since it's outdated

[vincbeck]

Looks good, just noticed this pattern is also present in example_google_api_youtube_to_s3:

airflow/providers/amazon/tests/system/amazon/aws/example_google_api_youtube_to_s3.py

Lines 99 to 107 in b5547c4

	make_authenticated_rest_api_request(
	path="/api/v2/connections",
	method="POST",
	body={
	"connection_id": conn_id_name,
	"conn_type": "google_cloud_platform",
	"extra": json.dumps(conn_extra),
	},
	)

I know we don't run this test on our dashboard but it might be good to get rid of the pattern entirely from the codebase since it's outdated

I agree, it does not hurt