Fixed mistake in comment

Author: EdAbati

scripts/validate_docstrings.py

@@ -480,7 +480,7 @@ def parameter_desc_list(self, param):
         desc_list = [line
                      # The 'Parameters' value of NumpyDocString._parsed_data is
                      # a list of tuples. Each tuple represents a parameter
-                     # docstring parameter and have the description of
+                     # docstring parameter and has the description of
                      # the parameter as last element.
                      for line in self.doc._parsed_data['Parameters'][i][-1]
                      if line]