Upgrade iperf3 to 3.18

[mfeit-internet2]

ESnet (Energy Sciences Network) is proud to announce the release of
iperf-3.18. This release includes several bug fixes, including one
that could cause an iperf3 server to crash if fed malformed data on
the control connection. For more information, please see:

https://downloads.es.net/pub/iperf/esnet-secadv-2024-0002.txt.asc

ESnet would like to thank Leonid Krolle Bi.Zone. for bringing this
issue to our attention.

More information on those changes can be found in the
iperf-3.18 release notes, which are contained in the RELNOTES.md file
in the distribution.

iperf-3.18 should be fully backward-compatible with prior iperf3
releases, that is, iperf-3.18 clients and servers should
interoperate correctly with all 3.x clients and servers.

The source code for iperf-3.18 is available at:

https://downloads.es.net/pub/iperf/iperf-3.18.tar.gz

SHA256 hash:

c0618175514331e766522500e20c94bfb293b4424eb27d7207fb427b88d20bab

iperf3 is freely-redistributable under a 3-clause BSD license.  More
information can be found in the LICENSE file inside the source
distribution.

Additional documentation: https://software.es.net/iperf

Source code and issue tracker: https://github.com/esnet/iperf

Discussion forums: https://github.com/esnet/iperf/discussions

Reporting security issues: [[email protected]](mailto:[email protected])

User questions can go to the iperf users list (which is more-or-less
shared between iperf2 and iperf3):

[[email protected]](mailto:[email protected])

Mailing list information and archives can be found at:

https://lists.sourceforge.net/lists/listinfo/iperf-users

The mailing list for iperf3 development is:

[[email protected]](mailto:[email protected])

To see the list archives or join the mailing list, visit:

http://groups.google.com/group/iperf-dev