Add hash to auto security group name for uniqueness

Node group id is unique enough to avoid duplicates.

Change-Id: I24b003fea3d7b610c91a4bf9c3f887a7b61cedf5
Closes-Bug: #1383348
(cherry picked from commit 230f105a0e5cdc7e758edc07f0628f2d68feb7d0)
Merge "Add hash to auto security group name for uniqueness" into stable/juno