chore(python): add docstring for limit behavior (#800)

Closes #796

python/tests/test_table.py

@@ -569,6 +569,14 @@ def test_empty_query(db):
     val = df.id.iloc[0]
     assert val == 1
 
+    table = LanceTable.create(db, "my_table2", data=[{"id": i} for i in range(100)])
+    df = table.search().select(["id"]).to_pandas()
+    assert len(df) == 10
+    df = table.search().select(["id"]).limit(None).to_pandas()
+    assert len(df) == 100
+    df = table.search().select(["id"]).limit(-1).to_pandas()
+    assert len(df) == 100
+
 
 def test_compact_cleanup(db):
     table = LanceTable.create(