Merge branch 'feature/add_gitmodules' into 'master'

update gitlab conf

See merge request !28

.gitlab-ci.yml

@@ -9,6 +9,7 @@ upload:
     TWINE_USERNAME: gitlab-ci-token
     TWINE_PASSWORD: $CI_JOB_TOKEN
     PYPI_REPO: $CI_API_V4_URL/projects/$CI_PROJECT_ID/packages/pypi
+    GIT_SUBMODULE_STRATEGY: recursive
   script:
     - apk add bash make gcc g++ linux-headers musl-dev libffi-dev
     - make release