TST: use default_rng to satisfy Ruff NPY002

Author: evgenii

pandas/tests/plotting/frame/test_linecollection_speedup.py

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+"""
+Ensure wide DataFrame.line plots use a single LineCollection
+instead of one Line2D per column (PR #61764).
+"""
+
+from matplotlib.collections import LineCollection
+import matplotlib.pyplot as plt
+import numpy as np
+
+import pandas as pd
+
+
+def test_linecollection_used_for_wide_dataframe():
+    rng = np.random.default_rng(0)
+    df = pd.DataFrame(rng.standard_normal((10, 201)).cumsum(axis=0))
+
+    ax = df.plot(legend=False)
+
+    # one LineCollection, zero Line2D objects
+    assert sum(isinstance(c, LineCollection) for c in ax.collections) == 1
+    assert len(ax.lines) == 0
+
+    plt.close(ax.figure)