Clone submodules only for the Bats test.

It's now in the CI template, so not necessary at all. But will only
happen in the Bats test so everything else should be a little faster.

.gitlab-ci.yml

@@ -7,9 +7,6 @@ include:
   - project: shore/ci-templates
     file: templates/gitlab-release.yml
 
-variables:
-  GIT_SUBMODULE_STRATEGY: recursive
-
 build-wheel:
   extends: .python3-build
   script: