Don't untar existing data

.gitlab-ci.yml

@@ -18,7 +18,7 @@ before_script:
   - apt-get update && apt-get install -y nodejs python3-pip
   - python3 -m pip install cwltool cwl-runner
   - cd test_data
-  - tar -xf ${TEST_DATASET_NAME}
+  - tar -kxf ${TEST_DATASET_NAME} 2> /dev/null || true
   - cd $CI_PROJECT_DIR
   - source /opt/bashrc