[docker] Fix tabs in Dockerfile.fedora
[docker] Fix tabs in Dockerfile.fedora

My editor was expanding tabs to spaces when other lines seem to be using pure tabs.
This is a cosmetic change that will align the indentation with the rest of the
file and at the same time exercise #4221

iovisor/bcc,iovisor/bcc,iovisor/bcc,iovisor/bcc,iovisor/bcc