message: remove irrelevant header files
diff: #include "duckdb/function/scalar/string_functions.hpp"
  -
  -#include "duckdb/common/exception.hpp"
  #include "duckdb/common/vector_operations/vector_operations.hpp"
  -#include "duckdb/common/vector_operations/ternary_executor.hpp"
  #include <string.h>
  #include <ctype.h>
  -#include <unordered_map>
  -#include <algorithm> // std::max
  -#include <iostream>
  +#include <algorithm> // std::max and std::min
  using namespace std;
  