Fixed failing test which was ignoring a required (not null) column (#26303)

* Fixed failing test which was ignoring a required (not null) column

* restored test to original, catching DriverException which also catches ConstraintViolationException

* catch ConstraintViolationException again

* removed unnecessary field from this test

* clobfield should be nullable

* clobfield now is nullable

* removed autoincrement since whenever this strategy is enabled, oracle would not throw constraint violation exceptions (needed for setValues), which mysql still does

* this field does not auto increment anymore

* mark integerfield as primary, since it is not getting marked as such through auto increment anymore,
integerfield default always has been 0 instead of null

Signed-off-by: Morris Jobke <hey@morrisjobke.de>