fix bug

app/controllers/concerns/git_helper.rb

@@ -9,17 +9,17 @@ module GitHelper
   # 版本库文件内容，带转码
   def git_fle_content(repo_path, path)
     begin
-      logger.info("git file content: repo_path is #{repo_path}, path is #{path}")
+      Rails.logger.info("git file content: repo_path is #{repo_path}, path is #{path}")
       content = GitService.file_content(repo_path: repo_path, path: path)
 
-      logger.info("git file content: content is #{content}")
+      Rails.logger.info("git file content: content is #{content}")
       decode_content = nil
       if content.present?
         content = content["content"]   #6.24 -hs 这个为新增，因为当实训题里含有选择题时，这里会报错,undefined method `[]' for nil:NilClass
 
         content = Base64.decode64(content)
         cd = CharDet.detect(content)
-        logger.info "encoding: #{cd['encoding']} confidence: #{cd['confidence']}"
+        Rails.logger.info "encoding: #{cd['encoding']} confidence: #{cd['confidence']}"
 
         decode_content =
             if cd["encoding"] == 'GB18030' && cd['confidence'] > 0.8