Fix clang compilation issue

[krzyw1x]

Fix for build issues with homebrew clang-19:

/opt/homebrew/Cellar/llvm/19.1.4/bin/../include/c++/v1/__memory/allocator.h:95:17: error: static assertion failed due to requirement '!is_const<const std::string>::value': std::allocator does not support const types
   95 |   static_assert(!is_const<_Tp>::value, "std::allocator does not support const types");
      |                 ^~~~~~~~~~~~~~~~~~~~~

You can find description of the problem here: https://stackoverflow.com/questions/21365331/which-is-correct-vectorconst-string-or-const-vectorstring

[ifratric]

Thanks!