fix: resolve cutQuotedString issue with double backslashes (\\)

[trgalho]

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This PR addresses an issue in the corazawaf cutQuotedString function where the presence of backslashes (\\) in the operator value prevents proper parsing of the SecRule. This parsing failure leads to load configuration errors and does not allow users to write certain rules for corazawaf, resulting in potential misconfigurations.

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 84.37%. Comparing base (4141903) to head (f11941e).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1364      +/-   ##
==========================================
+ Coverage   84.36%   84.37%   +0.01%     
==========================================
  Files         170      170              
  Lines        9925     9933       +8     
==========================================
+ Hits         8373     8381       +8     
  Misses       1308     1308              
  Partials      244      244              

Flag	Coverage Δ
coraza.rule.case_sensitive_args_keys	84.33% <100.00%> (+0.01%)	⬆️
coraza.rule.multiphase_evaluation	84.03% <100.00%> (+0.01%)	⬆️
coraza.rule.no_regex_multiline	84.31% <100.00%> (+0.01%)	⬆️
default	84.37% <100.00%> (+0.01%)	⬆️
examples+	16.33% <55.55%> (+0.04%)	⬆️
examples+coraza.rule.case_sensitive_args_keys	84.33% <100.00%> (+0.01%)	⬆️
examples+coraza.rule.multiphase_evaluation	83.87% <100.00%> (+0.01%)	⬆️
examples+coraza.rule.no_regex_multiline	84.23% <100.00%> (+0.01%)	⬆️
examples+memoize_builders	84.34% <100.00%> (+0.01%)	⬆️
examples+no_fs_access	?
ftw	84.37% <100.00%> (+0.01%)	⬆️
memoize_builders	84.47% <100.00%> (+0.01%)	⬆️
no_fs_access	83.87% <100.00%> (+0.01%)	⬆️
tinygo	84.34% <100.00%> (+0.01%)	⬆️

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[fzipi]

nit: update variable name.

Other than that, LGTM.