Fix yml-based translations to match format of wiki-based translations

For the wiki-based translations, we use symbols as keys for individual fields of translated content. This makes ensures the yml-based module and slide translations have the same key format, so that they will actually render.

app/models/training_module.rb

@@ -112,7 +112,7 @@ def inflate_content_hash(content)
     self.name = content['name'] || content[:name]
     self.description = content['description'] || content[:description]
     self.estimated_ttc = content['estimated_ttc']
-    self.translations = content['translations']
+    self.translations = TrainingBase.format_translation_keys content['translations']
     self.settings = content['settings']
     self.slide_slugs = content['slides'].pluck('slug')
   end

lib/training/training_base.rb

@@ -43,6 +43,17 @@ def self.training_loader_class
     Features.wiki_trainings? ? WikiTrainingLoader : YamlTrainingLoader
   end
 
+  # Takes a hash of translations and turns the keys within each
+  # locale into symbols, so that yml-based translations will have
+  # the same format as wiki-based translations.
+  def self.format_translation_keys(translations_hash)
+    return unless translations_hash
+    translations_hash.each_key do |locale_key|
+      translations_hash[locale_key] = translations_hash[locale_key].transform_keys(&:to_sym)
+    end
+    translations_hash
+  end
+
   class DuplicateSlugError < StandardError
   end
 end