compare a single file across two commits in the same branch
Description
At the moment GitLab can show a compare across commits, but when the commit contains multiple files, this can result in a "large" web page.
In the situation where there are multiple files changed in the commit, being able to inspect the changes in a single file would result in a smaller (faster to render) page and by not having the other files there would be simpler for collaboration
Proposal
Add the capability to compare single files across commits