Update OMNIBUS_GITLAB_CACHE_EDITION to Ruby 3.2

Ruby 3.2 has been made the default in
https://gitlab.com/gitlab-org/gitlab/-/merge_requests/168129

, but we
missed to update the omnibus-gitlab cache key.

Signed-off-by: Balasankar "Balu" C <balasankar@gitlab.com>

.gitlab-ci.yml

@@ -31,7 +31,7 @@ default:
 
 .default-ruby-variables: &default-ruby-variables
   RUBY_VERSION: "${RUBY_VERSION_DEFAULT}"
-  OMNIBUS_GITLAB_CACHE_EDITION: "GITLAB_RUBY3_1"
+  OMNIBUS_GITLAB_CACHE_EDITION: "GITLAB_RUBY3_2"
 
 .next-ruby-variables: &next-ruby-variables
   RUBY_VERSION: "${RUBY_VERSION_NEXT}"