**Describe the bug** Some early versions of isort are not compatible with the rest of the auto formatting tools, https://github.com/Project-MONAI/MONAI/blob/be3d13869d9e0060d17a794d97d528d4e4dcc1fc/requirements-dev.txt#L23 The requirement should have a minimal version constraint Cc @myron
