Upgrade sinatra to 2.0.3 silence audit for CVE-2018-11627
Upgrade sinatra to 2.0.3 silence audit for CVE-2018-11627

Running `rake bundle:audit` returned the following:

Name: sinatra
Version: 2.0.1
Advisory: CVE-2018-11627
Criticality: Unknown
URL: https://github.com/sinatra/sinatra/issues/1428
Title: XSS via the 400 Bad Request page
Solution: upgrade to >= 2.0.2

https://github.com/rubyforgood/new_sanctuary_asylum/issues/20

CZagrobelny/new_sanctuary_asylum,CZagrobelny/new_sanctuary_asylum,CZagrobelny/new_sanctuary_asylum,CZagrobelny/new_sanctuary_asylum