Remove deprecated plot_date calls

These were deprecated in Matplotlib 3.9.

Author: QuLogic

pandas/tests/plotting/test_datetimelike.py

@@ -1435,8 +1435,8 @@ def test_mpl_nopandas(self):
         kw = {"fmt": "-", "lw": 4}
 
         _, ax = mpl.pyplot.subplots()
-        ax.plot_date([x.toordinal() for x in dates], values1, **kw)
-        ax.plot_date([x.toordinal() for x in dates], values2, **kw)
+        ax.plot([x.toordinal() for x in dates], values1, **kw)
+        ax.plot([x.toordinal() for x in dates], values2, **kw)
 
         line1, line2 = ax.get_lines()