This is required to unbreak the fuzzers while a fix is being worked on.
https://cirrus-ci.com/task/4787303177519104?logs=ci#L3020
netaddress.cpp:1190:18: runtime error: implicit conversion from type 'int' of value -1 (32-bit, signed) to type 'uint8_t' (aka 'unsigned char') changed the value to 255 (8-bit, unsigned)