test: fix the system tests

See job: https://gitlab.cta-observatory.org/cta-computing/dpps/workload/CTADIRAC/-/jobs/386322

Tests are written in here: https://gitlab.cta-observatory.org/cta-computing/dpps/workload/CTADIRAC/-/blob/main/tests/system/runTestSuite.py?ref_type=heads

⚠️ need to use the pre-release branch for that.

• fix the tests and make the pipeline green (priority)
• Rewrite the tests: #131