add sleep after travis finishes to make sure it can send the info to travis-ci before shutting down VM

Author: wangjoshuah

.travis.yml

@@ -13,3 +13,6 @@ env:
 script:
   - if [[ "$TRAVIS_BRANCH" == "devel" ]]; then xcodebuild test -workspace OptimizelySDK.xcworkspace -scheme $SCHEME -configuration Debug CODE_SIGN_IDENTITY="" CODE_SIGNING_REQUIRED=NO -sdk $TEST_SDK -destination "platform=$PLATFORM,OS=$OS,name=$NAME"; fi
   - if [[ "$TRAVIS_BRANCH" == "master" ]]; then xcodebuild test -workspace OptimizelySDK.xcworkspace -scheme $SCHEME -configuration Release CODE_SIGN_IDENTITY="" CODE_SIGNING_REQUIRED=NO -sdk $TEST_SDK -destination "platform=$PLATFORM,OS=$OS,name=$NAME"; fi
+after_success:
+  - sleep 5 # https://github.com/travis-ci/travis-ci/issues/4725
+