Fix hostlocker parsing off-by-one
Fix hostlocker parsing off-by-one

When parsing the op-test configuration from a hostlocker machine blurb
we take a slice of all the lines following the '[op-test]' section
header and currently we drop the last line by accident.

The stop value in Python's slice notation isn't inclusive, so the slice
lines[offset:-1] won't include the last element in the list (at index -1).

I am really good at python.

Signed-off-by: Oliver O'Halloran <3dfaff8fa6ae977f042064a112a6aac576279b9b@gmail.com>

open-power/op-test-framework,open-power/op-test-framework,open-power/op-test-framework