Add Ukrainian localization files

config/locales/en.yml

-# Files in the config/locales directory are used for internationalization
-# and are automatically loaded by Rails. If you want to use locales other
-# than English, add the necessary files in this directory.
-#
-# To use the locales, use `I18n.t`:
-#
-#     I18n.t 'hello'
-#
-# In views, this is aliased to just `t`:
-#
-#     <%= t('hello') %>
-#
-# To use a different locale, set it with `I18n.locale`:
-#
-#     I18n.locale = :es
-#
-# This would use the information in config/locales/es.yml.
-#
-# The following keys must be escaped otherwise they will not be retrieved by
-# the default I18n backend:
-#
-# true, false, on, off, yes, no
-#
-# Instead, surround them with single quotes.
-#
-# en:
-#   'true': 'foo'
-#
-# To learn more, please read the Rails Internationalization guide
-# available at http://guides.rubyonrails.org/i18n.html.
-
 en:
-  hello: "Hello world"

config/locales/simple_form.uk.yml

+uk:
+  simple_form:
+    "yes": 'Так'
+    "no": 'Ні'
+    required:
+      text: "Обов'язкове поле"
+      mark: '*'
+    error_notification:
+      default_message: "Будь ласка, перевірте наступні помилки:"
\ No newline at end of file

config/locales/uk.yml

+uk: