I have found a serious problem in CubeMX 4.27 where cancelling the configuration
of a module containing DMA and interrupt settings will reset any configured interrupt
priority back to zero.
Step to duplicate the issue as follows.
Create an IOC file which has some module configured for DMA interrupts.
In System NVIC, set the DMA's interrupt with a non-zero preemption priority.
Open the module containing the DMA configuration and close again using 'OK'.
In System NVIC, check interrupt priority is still correct.
Open the module containing the DMA configuration and close again using 'Cancel'.
In System NVIC, check interrupt priority has been reset to zero.
