Resolution: Cannot Reproduce
This comes from
MDL-66260 (PHP 7.4 epic).
It has been detected that phpunit + php74 + oracle is behaving strangely / randomly, leading to a lot of failures without apparent explanation.
In the other side, local runs are mostly passing (there is 1 error and 1 failure, but likely it's my testing environment).
The same runs with any other database or any other php version pass without problems.
So initial target was to review that all the oracle-specific code (database driver) was php74 compliant. And it seems it is.
Worth mentioning that the very same combination of php74 + oracle is passing all behat tests without any problem.
So we need to investigate why this failures are happening. Could the docker images, could be some bogus test that is causing troubles at distance...
TODO1: Whenever we get this fixed, make all oracle phpunit jobs @ CI to go back to "highest".
TODO2: Also enable 38_STABLE highest to be PHP 7.4.
TODO3: Decide which database should be using intermediate PHP versions (right now PHP 7.3 in master).