[gimp-macos-build/wip/arcnor/tests] Update Xcode version to a supported CircleCI version

[Jehan <jehanp src gnome org>]

commit e14edd80c937cac7aa1cb851ccae248d947a9fcc
Author: Edu Garcia <arcnorj gmail com>
Date:   Fri Oct 8 15:16:27 2021 +0000

    Update Xcode version to a supported CircleCI version

 .circleci/config.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/.circleci/config.yml b/.circleci/config.yml
index c5d9095..88a4f75 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -2,7 +2,7 @@ version: 2
 jobs:
   build-gimp-2-10:
     macos:
-        xcode: "10.1.0"
+        xcode: "11.1.0"
 
     steps:
         - checkout