Fix reference to nonexistent ssh_connect_method in config help

The compute.ssh_connect_method option was replaced by the
validation.connect_method option. There is another option's
help which references ssh_connect_method though so this
cleans that up to avoid further confusion.

Change-Id: Ifb71314badcb41190cdaa0c4e780c0c5583f0c7b
1 file changed