build: update XCode version for CircleCI builds to 11.4.1 due to deprecations

Signed-off-by: deadprogram <ron@hybridgroup.com>

.circleci/config.yml

@@ -213,7 +213,7 @@ jobs:
           llvm: "12"
   build-macos:
     macos:
-      xcode: "11.1.0" # macOS 10.14
+      xcode: "11.4.1" # macOS 10.15.4
     steps:
       - build-macos