update --help text

Author: dlawin

data_diff/__main__.py

@@ -253,8 +253,8 @@ def write_usage(self, prog: str, args: str = "", prefix: Optional[str] = None) -
     "--select",
     "-s",
     default=None,
-    metavar="PATH",
-    help="select dbt resources to compare using dbt selection syntax.",
+    metavar="SELECTION or MODEL_NAME",
+    help="--select dbt resources to compare using dbt selection syntax in dbt versions >= 1.5.\nIn versions < 1.5, it will naively search for a model with MODEL_NAME as the name.",
 )
 @click.option(
     "--state",