[MM-24177] Adds props to post for front end to know if highlight or not (#14348)

* Add props to post

* Address PR comments

* address PR comments

* Fix styling problems

* Address PR comments

* address PR comments

* Add PR suggestion

* fix usage

* fix error

* remove err

* fix golang lint

app/post.go

@@ -396,6 +396,11 @@ func (a *App) FillInPostProps(post *model.Post, channel *model.Channel) *model.A
 		post.DelProp("channel_mentions")
 	}
 
+	matched := model.AT_MENTION_PATTEN.MatchString(post.Message)
+	if a.License() != nil && *a.License().Features.LDAPGroups && matched && !a.HasPermissionToChannel(post.UserId, post.ChannelId, model.PERMISSION_USE_GROUP_MENTIONS) {
+		post.AddProp(model.POST_PROPS_GROUP_HIGHLIGHT_DISABLED, true)
+	}
+
 	return nil
 }