Move brew installation of 7z only to deploy phase so it's not slowing…

… all PR builds

Also need to make udpate of homebrew as brew is not always up-to-date even if it is said so by Travis-CI

Change-Id: I07687daf561893e128566f8831baef1c37dd24d8
Signed-off-by: Florent Benoit <fbenoit@redhat.com>

.travis.yml

@@ -3,13 +3,11 @@ language: node_js
 node_js:
 - lts/*
 cache: yarn
-addons:
-  homebrew:
-    packages:
-    - p7zip
 before_install:
 - npm install -g pkg@4.3.8
 before_deploy:
+- brew update
+- brew install p7zip
 - git config --local user.name "Mario Loriedo"
 - git config --local user.email "mario.loriedo@gmail.com"
 - export TRAVIS_TAG=${TRAVIS_TAG:-$(date +'%Y%m%d%H%M%S')}