scancode-toolkit-mini 30.1.0 - missing dependency

### Description

When installing scancode-toolkit-mini in a clean system using pip it installs successfully, but produces this error when trying to execute it:

File "/Users/egans/PycharmProjects/scanoss.py/venv/lib/python3.8/site-packages/typecode/magic2.py", line 103, in load_lib_failover
ctypes.util.find_library('magic')
AttributeError: module 'ctypes' has no attribute 'util'

### How To Reproduce

Install on a clean system where scancode has not been installed before.

`pip install scancode-toolkit-mini
scancode --help
`

If you install the full version (pip install scancode-toolkit), uninstall and then re-install mini (pip install scancode-toolkit-mini), it will work. When you do this, the following extra packages get installed:

extractcode-30.0.0 extractcode-7z-16.5.210531 extractcode-libarchive-3.5.1.210531 patch-1.16 scancode-toolkit-30.1.0 typecode-libmagic-5.39.210531

I believe the "mini" install is missing "typecode-libmagic" package dependency.

### System configuration

* What OS are you running on? - MacOS & Linux
* What version of scancode-toolkit was used to generate the scan file? - 30.1.0, 21.8.4
* What installation method was used to install/run scancode? - pip