On the RBD driver, when doing a disconnect call inside a container, when
the "rbd_common" package is installed on the host, we can get a "No such
file or directory" error if the udev rule from the host removes the
symlink before we do.
This error is caused by the rm command returning 1 for different type of
errors, so we'll now use -f to ensure we don't fail if the file is
missing, which is what we intended before when passing the
check_exit_code parameter to the execute call.
Trivial-Fix
Closes-Bug: #1885293
Change-Id: Id1655614a8a60fba8ed225c6cea53ae1ed4b694a
efcec1d0ee