chore(skipmaskmanager): remove skip mask files at startup if no frac

[forshev]

Description

Now skip mask manager checks at startup whether existing skipmask file has corresponding fraction. If not, skip mask file is removed

Fixes #426

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[codecov-commenter]

Codecov Report

❌ Patch coverage is 41.17647% with 10 lines in your changes missing coverage. Please review.
✅ Project coverage is 70.58%. Comparing base (2c48a62) to head (a69a4ef).

Files with missing lines	Patch %	Lines
skipmaskmanager/skip_mask_manager.go	41.17%	10 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #427      +/-   ##
==========================================
- Coverage   70.65%   70.58%   -0.07%     
==========================================
  Files         219      219              
  Lines       17009    17021      +12     
==========================================
- Hits        12017    12015       -2     
- Misses       4094     4107      +13     
- Partials      898      899       +1     

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[eguguchkin]

nit: I'm kind of scared to delete RemoveAll — what if for some reason name == ""? Then the entire directory will be deleted :)

[forshev]

thanks. fixed