Run postgresql unit tests with valgrind only on scheduled builds
Summary
Also took the liberty of cleaning up some variables.
Once this has been merged, the nightly pipelines should be updated to set the VALGRIND_DB_UNIT_TESTS to true.
Additional Required Actions
- Requires manual tests in pre-production: NO
- Requires a documentation update: NO
References
Closes #924 (closed)
Edited by Niels Alexander Buegel