[gimp-macos-build] Increment cache number to force rebuild

[Alex Samorukov <asamorukov src gnome org>]

commit ac5850e037411bc75a89da378e4ca7da1ee377a9
Author: Oleksii Samorukov <oleksii_samorukov mckinsey com>
Date:   Wed Jan 15 18:14:05 2020 +0100

    Increment cache number to force rebuild

 .circleci/config.yml | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/.circleci/config.yml b/.circleci/config.yml
index 26b2cd1..2c89075 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -57,7 +57,7 @@ jobs:
         # we can try to make it automatically depended on the corresponding modules
         - restore_cache:
             keys:
-              - gimp-2.10.14-v14
+              - gimp-2.10.14-v15
               - webkit-v19
               - gimp-deps-v8
               - bootstrap-v18
@@ -114,7 +114,7 @@ jobs:
         - save_cache:
             paths:
               - ~/gtk
-            key: gimp-2.10.14-v14
+            key: gimp-2.10.14-v15
         - run:
             name: Importing signing certificate
             command: |