allow editing file/folder name in react_files

closes: CNVS-14670

test plan:
click the cog to edit a file or folder name,
it should work

Change-Id: I25eedea8bd2270ded67e1156de61caf696931b18
Reviewed-on: https://gerrit.instructure.com/38922
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Jason Madsen <jmadsen@instructure.com>
Product-Review: Ryan Shaw <ryan@instructure.com>
QA-Review: Ryan Shaw <ryan@instructure.com>