namcap.py: add a missing import
Fix the following error:
$ ./namcap-devel
Traceback (most recent call last):
File "/usr/lib/python3.10/runpy.py", line 196, in _run_module_as_main
return _run_code(code, main_globals, None,
File "/usr/lib/python3.10/runpy.py", line 86, in _run_code
exec(code, run_globals)
File "/home/yen/tmp/namcap/namcap.py", line 160, in <module>
modules = get_modules()
File "/home/yen/tmp/namcap/namcap.py", line 18, in get_modules
return Namcap.rules.all_rules
AttributeError: module 'Namcap' has no attribute 'rules'
I'm not sure why it worked. Probably Namcap.rules is imported somewhere implicitly, and it's no longer the case after wildcard imports are dropped in !32 (merged).