Add axhline to ax3

Author: CozyFrog

lib/matplotlib/tests/test_datetime.py

@@ -38,6 +38,7 @@ def test_axhline(self):
                      top=datetime.datetime(2023, 11, 1))
         ax1.axhline(y=datetime.datetime(2020, 6, 3), xmin=0.5, xmax=0.7)
         ax2.axhline(np.datetime64('2005-02-25T03:30'), xmin=0.1, xmax=0.9)
+        ax3.axhline(y=datetime.datetime(2023, 10, 24), xmin=0.4, xmax=0.7)
 
     @pytest.mark.xfail(reason="Test for axhspan not written yet")
     @mpl.style.context("default")