Refactor edit_on_gitlab helper
Rather than having a bunch of case statements with URLs, this changes
the edit_on_gitlab
helper so that it builds urls from a project path,
a branch name, and a docs file path. This is easier to maintain since
it's a data-driven approach. The PRODUCT_REPOS data can be edited
without changing the program logic.
Also:
- There weren't any tests, so I added some.
- I changed the blob path from the legacy
/:namespace/blob/:file
path to the modern/:namespace/-/blob/:file
path
Edited by Brian Williams