Feature: use use C++ std::string::compare in StringContent::compareString

[mcakircali]

replace strcmp (called in StringContent::compareString method) with string compare()

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 63.74%. Comparing base (2cf7ebe) to head (4b4cf79).

Additional details and impacted files

@@             Coverage Diff             @@
##           develop     #156      +/-   ##
===========================================
- Coverage    63.74%   63.74%   -0.01%     
===========================================
  Files         1066     1066              
  Lines        55360    55360              
  Branches      4086     4086              
===========================================
- Hits         35289    35287       -2     
- Misses       20071    20073       +2     

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