Restore formatting of _undercloud instructions

Somewhere in the past this block of instructions had its formatting
broken, leading it to it displaying inline without markup indicating it
as being a literal block of commands to run on the shell.

This change is intended to restore the formatting to match the other
instruction blocks.

Change-Id: I8a0a55cfa1c3a8ffc671fab14d09dca72e874690
Merge "Restore formatting of _undercloud instructions"