Organize the field options in a separated field group

MR created with that: https://git.drupalcode.org/project/ebt_basic_button/-/merge_requests/3

Now the fields related to Link are grouped in a new field group called Link options

Hi RenatoG, I agree it looks cleaner! I will test it before 1.4.0 release, because we need to save existing values for sites which are using 1.3.x branch now. I will take care of it. Thank you!