Zeek JA4H hashes an empty string instead of outputting 0000s

[john-althouse]

Bug in JA4H on Zeek, when there's no cookie, it's supposed to output 0000's, like po10nn060000_cdb958d032b0_000000000000_000000000000 But instead it's hashing an empty string so it does: po10nn060000_cdb958d032b0_e3b0c44298fc_e3b0c44298fc