FEATURE: Add Oracle Database to the CI tests

[RasmusSkytte]

Describe the feature
An additional code-coverage run using the Oracle Database as backend

What use will this feature have?
Wider DB support

Who should add the feature?
N/A

Additional context
N/A

[RasmusSkytte]

Working on the implementation over at https://github.com/ssi-dk/AEF-DDF/

[RasmusSkytte]

A Oracle Database is now up and running in the CI job, but I still need to correctly connect to it.

[RasmusSkytte]

CI should now connect to the Oracle database

All we need is to merge #186 to start developing Oracle Database support via RJDBC