Update .travis.yml

.travis.yml

@@ -12,7 +12,7 @@ notifications:
     on_start: false
 deploy:
   provider: releases
-  draft: true
+  prerelease: true
   api_key:
     secure: ZjE1j93v3qbPIe2YbmhS319aCbMdLQw0HuymmluTurxXsZtn9D4t2+eTr99vBVxGRuB5lzzGezPR5zjk5W7iHF7xhwrawXrFzr2rPJWzWFt0aM+Ry2njU1ROTGGXGTbv4anWeBlgMxLEInTAy/9ytOGNJlec83yc0THpOY2wxnk=
   file: main/uber-jar/target/Cryptomator-$TRAVIS_TAG.jar