Tools: install-prereqs-ubuntu.sh: fix script after setuptools>=71.0.0 release

[ben-xD]

Explicitly upgrade to use newest packaging to avoid packaging incompatibility with setuptools>=71.0

As pypa/setuptools#4496 (comment) mentions:

setuptools>=71.0 does not work with packaging<24.0, but will not upgrade it if packaging is already installed

Also relevant: pypa/setuptools#4496

[khancyr]

LGTM, just need to fix the install on focal

[peterbarker]

I've merged this as it fixes the Jammy environment test.

We should follow up with a fix for Focal as Pierre suggests, but it is a separate problem

Thanks @ben-xD !

[rmackay9]

I tried to include this in 4.5.6-beta1 but was unable to due to a merge conflict. If someone is keen on including this in 4.5 then a backport PR would be greatly appreciated!

[ben-xD]

@rmackay9, does that mean testing the changes and opening 1 PR for each of the branches:

  remotes/upstream/Copter-4.5                     9a755a82d7 Plane: version to 4.5.7-beta1
  remotes/upstream/Plane-4.5                      0523b2c7cf Plane: version to 4.5.7-beta1
  remotes/upstream/Rover-4.5                      7b5ef6df77 Plane: version to 4.5.7-beta1
  remotes/upstream/Sub-4.5                        cede211a7c CI: add navigator64 build
  remotes/upstream/Tracker-4.5                    22e8f1e84e Plane: version to 4.5.7-beta1