Update dnf.md run final sudo command with --disablerepo=*

[ThatTotallyRealMyth]

When running this on a system without internet connectivity, it is unable to actually execute and install the package created above. It is neccesary to include --disablerepo=* as there are instances where the exploit chain wont continue without while there's never a situation where your exploit chain wont work if the --disablerepo=* is included