[gimp-macos-build/xcodetest] use 11.1 instead

[Alex Samorukov <asamorukov src gnome org>]

commit 9346c229c3faef355204e4d4b7800bb7552a0546
Author: Oleksii Samorukov <oleksii_samorukov mckinsey com>
Date:   Thu Oct 31 16:50:35 2019 +0100

    use 11.1 instead

 .circleci/config.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/.circleci/config.yml b/.circleci/config.yml
index a41ab3e..7bc012d 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -2,7 +2,7 @@ version: 2
 jobs:
   build-gimp-2-10:
     macos:
-        xcode: "10.0.0"
+        xcode: "11.1.0"
 
     steps:
         - checkout