iperf3: updated versions from 3.6 to 3.16

[dmagdavector]

Spack currently only explicitly has version 3.6 of the iPerf3 package (out of ESnet / LBNL). This makes the default the latest version of 3.16, and adds some other versions (found in some Linux distros, for possible compatibility purposes).

closes #44096

[spackbot-app]

Hi @dmagdavector! I noticed that the following package(s) don't yet have maintainers:

• iperf3

Are you interested in adopting any of these package(s)? If so, simply add the following to the package class:

    maintainers("dmagdavector")

If not, could you contact the developers of this package and see if they are interested? You can quickly see who has worked on a package with spack blame:

$ spack blame iperf3

Thank you for your help! Please don't add maintainers without their consent.

You don't have to be a Spack expert or package developer in order to be a "maintainer," it just gives us a list of users willing to review PRs or debug issues relating to this package. A package can have multiple maintainers; just add a list of GitHub handles of anyone who wants to volunteer.

[wdconinc]

Please feel free to re-request a review when the new version and hash are here. I don't see any other issues.

[wdconinc]

Looks good. Thanks for the contribution!

[wdconinc]

Could you file the protobuf change as a separate PR please?

[dmagdavector]

Could you file the protobuf change as a separate PR please?

Mis-click / mis-merge on my part: that was my original intention: #44210

[wdconinc]

Can you git revert 4d168d0? Then we can get back to merging this here.