Fix failed integration test test_migrate_external_tables_with_spn_azure (#1496)

## Changes
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Not sure why didn't the integration test run in PR #1413 catch the
failure of this test `test_migrate_external_tables_with_spn_azure`, but
we need this fix to avoid the `ValueError: too many values to unpack
(expected 2)` error.

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Resolves #1497

Author: qziyuan

tests/integration/hive_metastore/test_migrate.py

@@ -493,7 +493,7 @@ def test_migrate_external_tables_with_spn_azure(
 ):
     if not ws.config.is_azure:
         pytest.skip("temporary: only works in azure test env")
-    ctx, table_full_name = prepared_principal_acl
+    ctx, table_full_name, _, _ = prepared_principal_acl
     cluster = make_cluster(single_node=True, spark_conf=_SPARK_CONF, data_security_mode=DataSecurityMode.NONE)
     ctx.with_dummy_resource_permission()