net/relayd: Regenerate checksums

It turns out that in the last round of testing I did not regenerate the
checksums correctly. Fixing it now.

MFH: 2023Q3
Sponsored by: Modirum MDPay
Sponsored by: Klara, Inc.

(cherry picked from commit 886e5793aec56a0eb4143f413da3e62a80eba372)