New file/folder name bugfix

[neelesh7singh]

Fixes #1611
I have decreased the min width for sidebar__file-item-name--ellipsis class

I have verified that this pull request:

• has no linting errors (npm run lint)
• is from a uniquely-named feature branch and has been rebased on top of the latest master. (If I was asked to make more changes, I have made sure to rebase onto master then too)
• is descriptively named and links to an issue number, i.e. Fixes #123

[catarak]

Thanks for fixing this! Looks great to me.