Sync for checkout

Former-commit-id: 00aa003a897612a47b020a18270f5a4225b3d027

.gitlab-ci.yml

@@ -31,6 +31,7 @@ before_script:
         echo "THIS SEEMS TO BE A MERGE PIPELINE FROM ${SOURCE_PROJECT}/${SOURCE_BRANCH}";
         git pull "https://gitlab.com/${SOURCE_PROJECT}/veloren.git" "${SOURCE_BRANCH}";
     fi;
+  - git submodule sync --recursive
   - git submodule update --init --recursive
   - git status
   - if [ -d target ]; then