chore(travis): Fix bad linebreak in previous commit

Author: naomiblack

scripts/travis/setup.sh

@@ -8,8 +8,7 @@ echo Fetch Dart channel: $CHANNEL
 DART_SDK_ZIP=dartsdk-linux-x64-release.zip
 
 echo http://storage.googleapis.com/dart-archive/channels/$CHANNEL/release/latest/sdk/$DART_SDK_ZIP
-curl -L http://storage.googleapis.com/dart-archive/channels/$CHANNEL/release/latest/sdk
-/$DART_SDK_ZIP > $DART_SDK_ZIP
+curl -L http://storage.googleapis.com/dart-archive/channels/$CHANNEL/release/latest/sdk/$DART_SDK_ZIP > $DART_SDK_ZIP
 echo Fetched new dart version $(unzip -p $DART_SDK_ZIP dart-sdk/version)
 rm -rf dart-sdk
 unzip $DART_SDK_ZIP > /dev/null