WIP: gitlab: add bug report template
https://docs.gitlab.com/ce/user/project/description_templates.html
Based off of @den.kos363's suggestion on the mailing list
@den.kos363: I'd prefer if you finished that DX instructions you started writing; otherwise I'll just leave it out and you can do an MR to add it when it's usable
Edited by Eric Engestrom