Fix UI.warning to UI.important

As `UI.warning` method doesn't exist - I wrote it from memory, should have checked the docs 😅

Author: AliSoftware

lib/fastlane/plugin/wpmreleasetoolkit/actions/ios/ios_lint_localizations.rb

@@ -58,7 +58,7 @@ def self.find_duplicated_keys(params)
             duplicates = Fastlane::Helper::Ios::StringsFileValidationHelper.find_duplicated_keys(file: path)
             duplicate_keys[language] = duplicates.map { |key, value| "`#{key}` was found at multiple lines: #{value.join(', ')}" } unless duplicates.empty?
           else
-            UI.warning <<~WRONG_FORMAT
+            UI.important <<~WRONG_FORMAT
               File `#{path}` is in #{file_type} format, while finding duplicate keys only make sense on files that are in ASCII-plist format.
               Since your files are in #{file_type} format, you should probably disable the `check_duplicate_keys` option from this `#{self.action_name}` call.
             WRONG_FORMAT

spec/ios_lint_localizations_spec.rb

@@ -187,7 +187,7 @@ def run_l10n_linter_test(data_file:, check_duplicate_keys: nil)
         File `#{fr_lproj}/Localizable.strings` is in xml format, while finding duplicate keys only make sense on files that are in ASCII-plist format.
         Since your files are in xml format, you should probably disable the `check_duplicate_keys` option from this `ios_lint_localizations` call.
       EXPECTED_WARNING
-      expect(FastlaneCore::UI).to receive(:warning).with(expected_message)
+      expect(FastlaneCore::UI).to receive(:important).with(expected_message)
 
       # Act
       install_dir = "vendor/swiftgen/#{Fastlane::Helper::Ios::L10nLinterHelper::SWIFTGEN_VERSION}"