- Update php dependencies to PHP 8.3
- Update the source code to inform version 1.5.23
- Update boca-web maintainer script for PHP 8.3
- Adds Ubuntu mirror to the standard jail
- Patch standard jail fixing debootstrap problems with Ubuntu noble
- Purge the unecessary packages in the jail
- Perform a dist-upgrade after updating the jail
- Quote shell variables o prevent suprise splitting
- Replace obsolete backticks with `$( )`
- Modernise test commands, replacing `[ ]` with `[[ ]]`

Explicitly declaring that the rules files does not require root access
will speed up the package compilation.

The boca-web package will not try to disable Apache's php8.1 module
(mod_php for PHP 8.1) anymore. It will conflict with the package that
provides the offending module for the distribution's current PHP
version, libapache2-mod-php.

The dependencies on PHP packages have been explicitly set to use PHP
version 8.1.

The boca-web post installation maintainer script has been updated with
extra descriptions and a the required steps to migrate from PHP 7.4.

The packages' long and short descriptions have been rewritten to address
the following errors, warnings and information found by Lintian:
* boca-autojudge: description-is-pkg-name BOCA - AutoJudge
* boca: description-starts-with-package-name
* boca: empty-binary-package
* boca: synopsis-is-a-sentence "BOCA is a software created to control a
  contest with the ACM ICPC rules.".

Debian Policy Manual section 3 states that a package is strongly advised
against depending on essential packages without except when explicitly
declaring a version constraint.

Essential packages are defined as "the minimal set of functionality that
must be available and usable on the system at all times" according to
the Debian Policy Manual section 3.8.

Given the reasons mentioned above, the dependencies on coreutils, an
essential package, have been removed from boca-common and
boca-submission-tools. This has also cleared the project from the
Lintian error `depends-on-essential-package-without-using-version`.

The Standards-Version is a mandatory field and its absence violates the
Debian Policy and generates an error on lintian (required-field).

Also check the lintian recommended documentation in case of a package
that has been detected by the `required-field` rule/tag:
* Debian Policy Manual section 5.3
* Debian Policy Manual section 5.5
* Debian Policy Manual section 5.6.11

The project already used debhelper, but it did not use the automatic
dependency and shared library finder.

Adding the expansion varibles `${misc:Depends}` and ${shlibs:Depends}`
solves this problem and the error found by lintian's static analysis
(missing-dependency-on-libc).