Fixed a statement in _attach_and_install to run as sudo.
Fixed a statement in _attach_and_install to run as sudo.

Discovered this while running the fab bootstrap on a clean box.


Former-commit-id: 6d04aec37873178ac4176e9ac363c7938e36ef75
gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine