Update main.yml

Author: igorkulman

.github/workflows/main.yml

@@ -10,6 +10,6 @@ jobs:
     steps:
     - uses: actions/checkout@v1
     - name: Install needed software
-      run: gem install xcpretty
+      run: gem install xcpretty && brew install swiftlint
     - name: Run tests
       run: xcodebuild test -project sources/LocalizationEditor.xcodeproj -scheme LocalizationEditor -destination 'platform=OS X,arch=x86_64' CODE_SIGN_IDENTITY="" CODE_SIGNING_REQUIRED=NO | xcpretty