Fix bug when viewing the commit diff page with non-ANSI files (#36149)#36150

wxiaoguang merged 2 commits intogo-gitea:release/v1.25go-gitea/gitea:release/v1.25from

wxiaoguang:fix-diff-charset-1.25wxiaoguang/gitea:fix-diff-charset-1.25Copy head branch name to clipboard