Implemented concurrent pipelines on Gitlab CI

.gitignore

.gitlab-ci-old.yaml

.gitlab-ci.yaml

docker-compose-ci.yml

hive/cli.py

hive/conf.py

scripts/ci/collect-db-stats.sh

scripts/ci/create-db.sh

scripts/ci/dump-db.sh

scripts/ci/get-postgres-version.sh

scripts/ci/hive-server.sh

scripts/ci/hive-sync.sh

scripts/ci/hived-node/config.ini

scripts/ci/hived-node/entrypoint.sh

scripts/ci/hived-node/run.sh

scripts/ci/postgres/10/Dockerfile

scripts/ci/postgres/12/Dockerfile

scripts/ci/python/3.6/Dockerfile

scripts/ci/python/3.8/Dockerfile

scripts/ci/start-api-smoketest.sh