fix(issues): use unified user display name pattern for more places (#39852)

* Fix #39761

---------

Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

models/issues/reaction.go

@@ -350,7 +350,7 @@ func (list ReactionList) GetFirstUsers() string {
 		if buffer.Len() > 0 {
 			buffer.WriteString(", ")
 		}
-		buffer.WriteString(reaction.User.Name)
+		buffer.WriteString(reaction.User.DisplayNameWithFullName())
 		if rem--; rem == 0 {
 			break
 		}