fix: ci with submodules

.gitlab/ci/build.gitlab-ci.yml

@@ -8,3 +8,5 @@ build:
     name: multi_user
     paths: 
      - multi_user
+  variables:
+    GIT_SUBMODULE_STRATEGY: recursive

.gitlab/ci/deploy.gitlab-ci.yml

@@ -5,6 +5,7 @@ deploy:
   variables:
     DOCKER_DRIVER: overlay2
     DOCKER_TLS_CERTDIR: "/certs"
+    GIT_SUBMODULE_STRATEGY: recursive
   
   services:
   - docker:19.03.12-dind

.gitlab/ci/test.gitlab-ci.yml

@@ -3,3 +3,5 @@ test:
   image: slumber/blender-addon-testing:latest
   script:
     - python3 scripts/test_addon.py
+  variables:
+    GIT_SUBMODULE_STRATEGY: recursive