Open folder variants for all folder icons

### Icon name folder-bookmark-open, folder-up-open, folder-key-open, folder-git-2-open, folder-symlink-open ### Use cases In my app I built a tree view and made use of lucide icons for the folder elements. Currently, I use various icons for specific kinds of folders (i.e. `folder-git-2` for one containing a git repo). It would be helpful if there were open variants for those icons so that I don't have to switch to the plain `folder-open` from those special icons. ### Design ideas Maybe similar to `folder-open-dot`, except the various design elements for the special folder icon kinds are placed there instead of the dot. ### Checklist - [x] I have searched if someone has submitted a similar issue before and there weren't any. (Please make sure to also search closed issues, as this issue might already have been resolved.) - [x] I have searched existing icons to make sure it does not already exist and I didn't find any. - [x] I am not requesting a brand logo and the art is not protected by copyright, see more at https://github.com/lucide-icons/lucide/blob/main/BRAND_LOGOS_STATEMENT.md - [x] I am not requesting an icon that includes religious, war/violence related, political imagery or hate symbols. - [x] I have provided appropriate use cases for the icon(s) requested.