Changed not to use string_view

httplib.h

@@ -2142,8 +2142,8 @@ inline constexpr unsigned int str2tag_core(const char *s, size_t l,
                                  (h * 33) ^ static_cast<unsigned char>(*s));
 }
 
-inline constexpr unsigned int str2tag(std::string_view sv) {
-  return str2tag_core(sv.data(), sv.size(), 0);
+inline constexpr unsigned int str2tag(const std::string &s) {
+  return str2tag_core(s.data(), s.size(), 0);
 }
 
 namespace udl {