Use homebrew addon in CI deploy stage instead of manual script lines

This change should be carefully "tested" with test release of next update.

Author: tsolomko

.travis.yml

@@ -40,14 +40,13 @@ jobs:
       osx_image: xcode10.1
       env:
         secure: 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
-      before_install:
-      - brew update
+      addons:
+        homebrew:
+          packages:
+          - carthage
+          - sourcekitten
+          update: true
       install:
-      # Update Carthage.
-      # `brew outdated` is necessary to prevent build error when there is no updates for Carthage.
-      - brew outdated carthage || brew upgrade carthage
-      # Install SourceKitten and Jazzy.
-      - brew install sourcekitten
       - gem install -N jazzy
       - gem update -N cocoapods
       before_deploy: