Update deps for CVE-2018-11627
Update deps for CVE-2018-11627

n.b. This CVE only requires an update for Sinatra but I've gone ahead
and patched all dependencies as we've not done this for some time.

ausaccessfed/saml-service,ausaccessfed/saml-service,ausaccessfed/saml-service,ausaccessfed/saml-service