chore(scan): Remove ._findings

[jfagoagas]

Description

Remove Scan._findings since it is not being used and only increases memory usage.

Checklist

• Are there new checks included in this PR? Yes / No
  • If so, do we need to update permissions for the provider? Please review this carefully.
• Review if the code is being covered by tests.
• Review if code is being documented following this specification https://github.com/google/styleguide/blob/gh-pages/pyguide.md#38-comments-and-docstrings
• Review if backport is needed.
• Review if is needed to change the Readme.md

License

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 89.37%. Comparing base (80fe048) to head (e770575).
Report is 4 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #6667      +/-   ##
==========================================
- Coverage   89.37%   89.37%   -0.01%     
==========================================
  Files        1182     1182              
  Lines       33817    33815       -2     
==========================================
- Hits        30225    30222       -3     
- Misses       3592     3593       +1     

Flag	Coverage Δ
prowler	89.37% <ø> (-0.01%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
prowler	89.37% <ø> (-0.01%)	⬇️
api	∅ <ø> (∅)