appview: remove unnecessary markdown config

appview/pages/markdown.go

···
 	"github.com/yuin/goldmark"
 	"github.com/yuin/goldmark/extension"
 	"github.com/yuin/goldmark/parser"
-	"github.com/yuin/goldmark/renderer/html"
 )
 
 func renderMarkdown(source string) string {
···
 		goldmark.WithExtensions(extension.GFM),
 		goldmark.WithParserOptions(
 			parser.WithAutoHeadingID(),
-		),
-		goldmark.WithRendererOptions(
-			html.WithHardWraps(),
-			html.WithXHTML(),
 		),
 	)
 	var buf bytes.Buffer