Merge pull request #94 from RxSwiftCommunity/update-circleci-config

update xcode version to 13.1.0 from 12.3.0

Author: ashfurrow

.circleci/config.yml

@@ -2,7 +2,7 @@ version: 2
 jobs:
   build-and-test:
     macos:
-      xcode: "12.3.0"
+      xcode: "13.1.0"
 
     steps:
       - checkout