Change SW360 integration tests to use backend only

[blaumeiser-at-bosch]

Summary of the Improvement

One big problem with the SW360 integration tests is the Postgres dump with JavaScript code from Liferay in it. This cannot be contributed due to license issues of that code. But the Liferay frontend is not needed for the integration tests. Therefore, the test should only start the backend with the CouchDB database and prefill this database prior to running the tests. This should be possible without any copyrighted stuff from a 3rd party.

Acceptance Criteria

• [ ] Switch the integration test setup to only use the SW360 backend and CouchDB
• [ ] Integrate the integration tests into the build

Definition of Done

• Acceptance criteria fulfilled
• The ticket describes what has been done and describes how the results can be verified (e.g. new Jenkins step is inserted, the report can be viewed at X)
• All known limitations are listed and it is described how they will be addressed (e.g., a ticket for the remaining stuff)
• Documentation is updated
• The result has been reviewed: Everything works as described and can be verified reading only the documentation