Add cache_info to benchmarking information in dlint.namespace

[mschwager]

functools.lru_cache was recently added to dlint.namespace which provided a great speed up. We should output functools.lru_cache.cache_info information when benchmarking.

We should be able to:

• Run the benchmarking code over a Python file
• Output linter.namespace.illegal_module_imported.cache_info
• Output linter.namespace.name_imported.cache_info
• Consider caching asname_to_name as well

Outputting cache_info will tell us if we're efficiently caching information, and can allow for greater profiling and speed ups.