Fix windows integration test
Fix windows integration test

- Update expected error message to succeed in windows tests too

[#152212273](https://www.pivotaltracker.com/story/show/152212273)

Signed-off-by: Bozhidar Lenchov <0c02b99b680f701f4c4a201b69ba2be691986624@pivotal.io>

cloudfoundry/bosh-agent,mattcui/bosh-agent,cloudfoundry/bosh-agent,gu-bin/bosh-agent,mattcui/bosh-agent,mattcui/bosh-agent,gu-bin/bosh-agent,gu-bin/bosh-agent