Updated Xcode to 11.4.1 for circle ci

Author: Fabian Muecke

.circleci/config.yml

@@ -9,7 +9,7 @@ jobs:
       XCODE_TEST_REPORTS: /tmp/xcode-test-results
       LANG: en_US.UTF-8
     macos:
-      xcode: '10.2.0'
+      xcode: '11.4.1'
     steps:
       - checkout
       - run: mkdir -p $CIRCLE_ARTIFACTS $CIRCLE_TEST_REPORTS $XCODE_TEST_REPORTS