I have tried to build an example STM32H7Cube project with a command line script (attached) and got that the each CM7 and CM4 project configuration is built twice: the "Release" for CM7 is built twice, then the "Debug" for CM7 is built twice, and then the same for CM4. The expected behavior is having one build per configuration per project.
STM32CubeH7/Projects/STM32H747I-DISCO/Examples/GPIO/GPIO_EXTI (master)
$ ./build_all.bat | grep 'Build'
Building All Projects...
Project: GPIO_EXTI doesn't appear to be a CDT project. Skipping...
11:23:18 **** Build of configuration Release for project GPIO_EXTI_CM7 ****
11:23:20 Build Finished. 0 errors, 0 warnings. (took 1s.946ms)
11:23:20 **** Build of configuration Release for project GPIO_EXTI_CM7 ****
11:23:20 Build Finished. 0 errors, 0 warnings. (took 246ms)
11:23:21 **** Build of configuration Debug for project GPIO_EXTI_CM7 ****
11:23:23 Build Finished. 0 errors, 0 warnings. (took 2s.35ms)
11:23:23 **** Build of configuration Debug for project GPIO_EXTI_CM7 ****
11:23:24 Build Finished. 0 errors, 0 warnings. (took 239ms)
11:23:24 **** Build of configuration Release for project GPIO_EXTI_CM4 ****
11:23:25 Build Finished. 0 errors, 0 warnings. (took 1s.437ms)
11:23:25 **** Build of configuration Release for project GPIO_EXTI_CM4 ****
11:23:25 Build Finished. 0 errors, 0 warnings. (took 243ms)
11:23:26 **** Build of configuration Debug for project GPIO_EXTI_CM4 ****
11:23:27 Build Finished. 0 errors, 0 warnings. (took 1s.713ms)
11:23:27 **** Build of configuration Debug for project GPIO_EXTI_CM4 ****
11:23:28 Build Finished. 0 errors, 0 warnings. (took 239ms)
