etc: Use git-file-name if origin is git-fetch....

Age	Commit message (Expand)	Author
2019-08-28	accounts: Delete duplicate entries....	Ludovic Courtès
2019-04-27	tests: Adjust accounts test to shell-as-config change....	Ludovic Courtès
2019-03-25	accounts: Add default value for the 'home-directory' field of <user-account>....	Ludovic Courtès
2019-03-07	Add (gnu build accounts)....	Ludovic Courtès
Pierre Neidhardt
2018-07-13	etc: snippets: Add guix-commit-message-use-https-home-page....	Arun Isaac
2018-07-13	etc: snippets: Add new build systems to package snippet....	Arun Isaac
2017-12-15	etc: Add snippets....	Ricardo Wurmus