Add munit_rand_uint32_range()

[esromneb]

Added because calling munit_rand_int_range(0, 0xffffffff); was only returning 0 or -1.

Not sure if you will actually accept this, but I'd love to help with documentation if you actually want this function or something similar

[jibsen]

Thanks for the contribution, I am sure nemequ will let you know if he is interested, but I just wanted to mention that for the specific range you mention there is munit_rand_uint32().