fix: removed unnecessary function, update header file for signature change.

src/util/has_8bit_hex.cpp

@@ -1,15 +0,0 @@
-#include <filesystem>
-#include <fstream>
-#include <regex>
-
-namespace fs = std::filesystem;
-
-bool has_8bit_hex(std::string file_path) {
-  std::ifstream f(file_path, std::ios::in | std::ios::binary);
-  const auto size = fs::file_size(file_path);
-  std::string result(size, '\0');
-  f.read(result.data(), size);
-  std::regex pattern(
-      R"((?:\#([a-fA-F0-9]{2})([a-fA-F0-9]{2})([a-fA-F0-9]{2})([a-fA-F0-9]{2})))");
-  return std::regex_search(result, pattern);
-}