Packages: added Ubuntu 24.04 "noble" support.

[en-jschuetze]

To make it possible to use the official nginx unit packages on the latest LTS from ubuntu, we need to have this packages build.

I searched through the repo and found this Makefile for building the packages. But afterwards we need to change also https://github.com/nginx/unit-docs/edit/master/source/installation.rst and see if the files really apply and are available at https://packages.nginx.org/unit/ubuntu/dists/

[thresheek]

I think it needs more changes to make it buildable on 24.04, e.g. FORTIFY_SOURCE needs a dance similar to what we implemented in nginx: https://hg.nginx.org/pkg-oss/rev/ce74bf99bf45

Also, I think the list of included Makefiles needs to be adapted to reflect the reality - e.g. there is no Python 3.11 shipped with 24.04; same for Java 19 and 20 as far as I can tell.

[thresheek]

A correct version is submitted at https://github.com/nginx/unit/pull/1287

[callahad]

Closing in favor of @thresheek's PR. Thank you for getting the ball rolling, @en-jschuetze :)