update version of rpmbuild

Author: apoorvam

.travis.yml

@@ -15,7 +15,7 @@ addons:
     - snapd
 before_install:
 - rpmbuild --version
-- sudo apt-get update -qq
+- sudo apt-get install -qq rpmbuild
 - rpmbuild --version
 - openssl aes-256-cbc -K $encrypted_12c8071d2874_key -iv $encrypted_12c8071d2874_iv
   -in snap.login.enc -out snap.login -d