Multiprocess pool refactored

[babenek]

Description

Please include a summary of the change and which is fixed.

• Used unordered_map to speedup a bit (~10%)
• Use splitted sequences of providers lists to utilize multiple processes efficency
  BEFORE:
  
  NOW:
  

How has this been tested?

Please describe the tests that you ran to verify your changes.

• UnitTest
• Benchmark after URL Credential pattern fix #580
• Run with --job $(nproc) and watch CPU utilization

[babenek]

@Samsung/credsweeper_maintainers , please review the PR

[xDizzix]

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 92.85714% with 1 line in your changes missing coverage. Please review.

Project coverage is 90.28%. Comparing base (9acea8b) to head (54591e7).

Files	Patch %	Lines
credsweeper/app.py	92.85%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #583      +/-   ##
==========================================
+ Coverage   90.23%   90.28%   +0.04%     
==========================================
  Files         131      131              
  Lines        4680     4683       +3     
  Branches      755      756       +1     
==========================================
+ Hits         4223     4228       +5     
+ Misses        304      302       -2     
  Partials      153      153              

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