configure.ac prints really old info

[barbeque-squared]

Copied from https://gitlab.alpinelinux.org/alpine/aports/-/merge_requests/77621 which is refenced by #940:

!!!
!!! Configuration of ultrastardx 2024.10.0 done!
!!!
!!! Type "make" to compile and
!!!      "make install" to install it afterwards.
!!!
!!! For further information on ultrastardx visit:
!!!   http://usdx.eu/
!!!
!!! In case you find a bug send a bugreport to:
!!!   https://github.com/UltraStar-Deluxe/USDX/issues/
!!! You might as well ask for help at the IRC-Channel
!!!   #usdx at freenode.net
!!!

Suggested changes:

• the website link should probably be https
• is the IRC channel even active? there are better solutions (like IRC/discord bridges) but for the time being it's probably an absolute improvement if we just direct them to usdx.eu/contact instead

should be pretty easy to fix, I just can't do it right now and otherwise I will forget about it entirely.