GitLab UI should handle two non-conflicting edits to a file

Proposal

Context: We met with an active academia user of GitLab's community edition. They use GitLab extensively, including to capture documentation and meeting agendas and notes.

The problem: When two people use the web UI to make updates to the same file and then try to merge their, non-conflicting, changes the web UI fails for them.

Request: From the requester: "gitlab UI should handle merges in commits as it works from a console push. Merging is a core git competence; two non-conflicting edits to a file through the UI should be merged rather than failing."