We call "apt-get upgrade" to apply changes related to ppa
of ZFS on linux. But "grub"-related packaged started making
dialog that hangs forever in case of automatic setup.
So, exclude "grub" related packages from update as redundant
for unblocking ZFSonLinux driver prerequisites setup.
Change-Id: Ibb94604710b0d4199825e770194655653c26bf89
Closes-Bug: #1609696