pcapy is no longer supported and does not work on Python 3.10 and 3.11
Also it's not used by forge. (Previously used by older versions of scapy)
Removing this dependency allows compatibility with Python 3.10 and 3.11
Tests: https://jenkins.aws.isc.org/view/Kea-manual/job/kea-manual/job/tarball-system-tests/199/