added first test of the load_data function

Author: wegar-2

tests/test_load_data.py

@@ -0,0 +1,17 @@
+import numpy as np
+import pandas as pd
+
+from moddata import load_data
+
+
+def test_load_data_bankchurn():
+    data: pd.DataFrame = load_data(dataset="bankchurn")
+    assert data.shape == (10_000, 12)
+    assert set(data.columns) == {
+        'customer_id', 'credit_score', 'country', 'gender', 'age', 'tenure',
+        'balance', 'products_number', 'credit_card', 'active_member',
+        'estimated_salary', 'churn'
+    }
+    assert data.at[17, "credit_card"] == np.int64(1)
+
+