Add native filetype + compression detection

[TheTechromancer]

This PR updates the FILESYSTEM event to autodetect the file content type and compression using magic bytes.

    # test filesystem event - file
    scan = Scanner()
    event = scan.make_event({"path": zip_file}, "FILESYSTEM", parent=scan.root_event)
    assert event.data == {
        "path": "/tmp/.bbottestzipasdkfjalsdf.zip",
        "magic_extension": ".zip",
        "magic_mime_type": "application/zip",
        "magic_description": "PKZIP Archive file",
        "magic_confidence": 0.9,
        "compression": "zip",
    }
    assert event.tags == {"file", "zip-archive", "compressed"}

    # test filesystem event - folder
    scan = Scanner()
    event = scan.make_event({"path": "/tmp"}, "FILESYSTEM", parent=scan.root_event)
    assert event.data == {"path": "/tmp"}
    assert event.tags == {"folder"}

@domwhewell-sage

[codecov]

Codecov Report

Attention: Patch coverage is 98.36066% with 1 line in your changes missing coverage. Please review.

Project coverage is 93%. Comparing base (72a250a) to head (1cb32e2).
Report is 6 commits behind head on dev.

Files with missing lines	Patch %	Lines
bbot/core/helpers/libmagic.py	92%	1 Missing ⚠️

Additional details and impacted files

@@          Coverage Diff          @@
##             dev   #1929   +/-   ##
=====================================
- Coverage     93%     93%   -0%     
=====================================
  Files        356     357    +1     
  Lines      27530   27580   +50     
=====================================
+ Hits       25389   25418   +29     
- Misses      2141    2162   +21     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.