Upgrade base Lubuntu ISO image to 22.04.2 with removing unnecessary packages and caches

[sanak]

Related with the following Trac tickets:

• #2429 (Base Lubuntu ISO image needs to be stored in somewhere) – OSGeoLive
• #467 (remove bulky orphaned packages) – OSGeoLive

Upgrading base Lubuntu ISO image to 22.04.2 caused over 4G error, so I am trying to remove the following packages and caches.

• apt packages
  • libicu-dev
  • libc6-dev
  • apt-xapian-index
• caches
  • /var/lib/apt/lists/*

[sanak]

I confirmed that ISO image fits the size limit (< max: 4GiB (=4,294,967,295 byte)).

stage	squashfs size (byte)	size diff from max limit (byte)
Before removing packages (1st commit)	4,393,156,608	+98,189,313
After removing libicu-dev and libc6-dev (2nd commit)	4,366,626,816	+71,659,521
After removing apt-xapian-index and /var/lib/apt/lists/* (3rd and 4th commits)	4,265,279,488	-29,687,807

There seems to be no error from quick glance, but I will check more in this weekend.
The built ISO image is here.
https://drive.google.com/file/d/1IcDryhO-BRySpi9LnNxfRDFlshYK5czh/view?usp=share_link