Fix: Change 'nullptr' to 'NULL' in strtok call

This change ensures that the code adheres to traditional C standards while maintaining the same functionality.

Signed-off-by: Kaiyao Duan <[email protected]>

tests/test_env_detect.cpp

@@ -17,7 +17,7 @@ bool is_option_disabled(const char* options, const char* option)
             disabled = true;
             break;
         }
-        token = strtok(nullptr, ",");
+        token = strtok(NULL, ",");
     }
 
     free(options_copy);