DEV: Update rubocop-discourse to version 3.8.0 (#292)

lib/discourse_data_explorer/data_explorer.rb

@@ -170,7 +170,7 @@ module ::DiscourseDataExplorer
       end
 
       needed_classes.each do |cls, column_nums|
-        next unless column_nums.present?
+        next if column_nums.blank?
         support_info = extra_data_pluck_fields[cls]
         next unless support_info
 

lib/discourse_data_explorer/parameter.rb

@@ -25,7 +25,7 @@ module ::DiscourseDataExplorer
       @default = default
       @nullable = nullable
       begin
-        cast_to_ruby default unless default.blank?
+        cast_to_ruby default if default.present?
       rescue ValidationError
         raise ValidationError.new(
                 "Parameter declaration error - the default value is not a valid #{type}",