Add integration tests adapted from legacy repo

.gitlab-ci.yml

.helmignore

Chart.lock

Chart.yaml

charts/vs-ingestor-0.1.2.tgz

charts/vs-ingestor-0.1.3.tgz

charts/vs-registrar-0.1.0.tgz

charts/vs-registrar-0.1.6.tgz

charts/vs-renderer-0.1.0.tgz

charts/vs-renderer-0.1.6.tgz

testing/Dockerfile

testing/preprocessed_list.csv

testing/product_list.csv

testing/product_list.json

testing/pvc-redis.yaml

testing/requirements.txt

testing/run_integration_test.sh

testing/test_ingestor.py

testing/test_preprocessor.py

testing/test_registrar.py