flent doesn't work with fping 5.1

Per https://github.com/tohojo/flent/issues/232, opening a new issue to track the fact that flent isn't happy with fping 5.1

Essentially, with Ubuntu server LTS, if you do "apt install flent fping" then flent isn't happy. To work around this issue, you can clone the latest flent, do "make install", and "apt install irrt", and flent will correctly use irrt.

das@3rd:~/Downloads/cake/cmd/run_qdiscs_tests$ /usr/bin/sudo /usr/sbin/ip netns exec network101 /usr/bin/flent rrul --output  /tmp/qdisc/2023-10-13T15:53:21/pi4/noqueue/flent/test/15_flent/flent_pi4_noqueue.png --data-dir /tmp/qdisc/2023-10-13T15:53:21/pi4/noqueue/flent/test/15_flent/ --format summary --plot all_scaled --title-extra 2023-10-13T15:53:21_pi4_noqueue --note 2023-10-13T15:53:21_pi4_noqueue --extended-metadata --host 172.17.51.10 --length 60 --ipv4 --socket-stats
Starting Flent 2.0.1 using Python 3.10.12.
Starting rrul test. Expected run time: 70 seconds.
WARNING: Found fping, but couldn't parse its output. Not using.              <---------------- ???
ERROR: Runner Ping (ms) ICMP failed check: Cannot parse output of the system ping binary (/usr/bin/ping). Please install fping v3.5+.    <----- ??

das@3rd:~/Downloads/cake/cmd/run_qdiscs_tests$ dpkg --list | grep ping
ii  fping                                 5.1-1                                   amd64        sends ICMP ECHO_REQUEST packets to network hosts
ii  iputils-ping                          3:20211215-1                            amd64        Tools to test the reachability of network hosts
ii  kpartx                                0.8.8-1ubuntu1.22.04.1                  amd64        create device mappings for partitions
ii  libharfbuzz0b:amd64                   2.7.4-1ubuntu3.1                        amd64        OpenType text shaping engine (shared library)

das@3rd:~/Downloads/cake/cmd/run_qdiscs_tests$ fping --version
fping: Version 5.1
das@3rd:~/Downloads/cake/cmd/run_qdiscs_tests$ ping -V
ping from iputils 20211215

das@3rd:~/Downloads/cake/cmd/run_qdiscs_tests$ cat /etc/lsb-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=22.04
DISTRIB_CODENAME=jammy
DISTRIB_DESCRIPTION="Ubuntu 22.04.3 LTS"

das@3rd:~$ fping -D -c 1 -r 0 -t 200 localhost 172.17.51.10 one.one.one.one
[1697477431.53507] localhost       : [0], 64 bytes, 0.013 ms (0.013 avg, 0% loss)
[1697477431.56876] one.one.one.one : [0], 64 bytes, 13.5 ms (13.5 avg, 0% loss)
[1697477431.74532] 172.17.51.10    : [0], timed out (NaN avg, 100% loss)

localhost       : xmt/rcv/%loss = 1/1/0%, min/avg/max = 0.013/0.013/0.013
172.17.51.10    : xmt/rcv/%loss = 1/0/100%
one.one.one.one : xmt/rcv/%loss = 1/1/0%, min/avg/max = 13.5/13.5/13.5

das@3rd:~$ /usr/bin/sudo /usr/sbin/ip netns exec network101 fping -D -c 1 -r 0 -t 200 localhost 172.17.51.10 one.one.one.one
one.one.one.one: Temporary failure in name resolution
[1697477514.39299] 172.17.51.10 : [0], 64 bytes, 60.6 ms (60.6 avg, 0% loss)
[1697477514.52249] localhost    : [0], timed out (NaN avg, 100% loss)

localhost    : xmt/rcv/%loss = 1/0/100%
172.17.51.10 : xmt/rcv/%loss = 1/1/0%, min/avg/max = 60.6/60.6/60.6

tohojo / flent

flent doesn't work with fping 5.1 #290