allign wording in description and error

Author: Kislovskiy

lib/matplotlib/axes/_axes.py

@@ -3294,7 +3294,7 @@ def has_negative_values(array):
 
         if has_negative_values(xerr) or has_negative_values(yerr):
             raise ValueError(
-                "'xerr' and 'yerr' must have non-negative numbers")
+                "'xerr' and 'yerr' must have non-negative values")
 
         if isinstance(errorevery, Integral):
             errorevery = (0, errorevery)

lib/matplotlib/tests/test_axes.py

@@ -3516,7 +3516,7 @@ def test_errorbar_every_invalid():
 def test_xerr_yerr_positive():
     ax = plt.figure().subplots()
 
-    error_message = "'xerr' and 'yerr' must have non-negative numbers"
+    error_message = "'xerr' and 'yerr' must have non-negative values"
 
     with pytest.raises(ValueError, match=error_message):
         ax.errorbar(x=[0], y=[0], xerr=[[-0.5], [1]], yerr=[[-0.5], [1]])