specify simulator for convex hull tests on travis

Author: mnespor

.travis.yml

@@ -20,7 +20,7 @@ script:
 - xcodebuild test -project ./Bucket\ Sort/Tests/Tests.xcodeproj -scheme Tests
 - xcodebuild test -project ./B-Tree/Tests/Tests.xcodeproj -scheme Tests
 - xcodebuild test -project ./Comb\ Sort/Tests/Tests.xcodeproj -scheme Tests
-- xcodebuild test -project ./Convex\ Hull/Convex\ Hull.xcodeproj -scheme Tests
+- xcodebuild test -project ./Convex\ Hull/Convex\ Hull.xcodeproj -scheme Tests -destination 'platform=iOS Simulator,name=iPhone 7,OS=11.0'
 - xcodebuild test -project ./Counting\ Sort/Tests/Tests.xcodeproj -scheme Tests
 - xcodebuild test -project ./Depth-First\ Search/Tests/Tests.xcodeproj -scheme Tests
 - xcodebuild test -project ./Graph/Graph.xcodeproj -scheme GraphTests