bug#72257: Non-English manuals for 1.4.0 are unavailable

["pelzflorian (Florian Pelz)" <pelzflorian@pelzflorian.de>]

Hello all, I do not understand why these old manuals are built with
po4a.cfg.  Why does it not use old guix 1.4.0 to build old manual 1.4.0?

po4a.cfg was added to guix.git in early June 2024 in commits starting from

commit 2d4af5247057505956e841d396ec78af9f769837
Author: gemmaro <gemmaro.dev@gmail.com>
Date:   Sun Apr 14 16:18:51 2024 +0900

    build: Update the POT creation task with the po4a command.
    
    * configure.ac (Documentation translation): Add the po4a program and remove
    the po4a-updatepo program.  The PO4A defined here can be used in
    Makefiles (e.g. po/doc/local.mk below).  The po4a command integrates the
    functionality of po4a-updatepo and is currently recommended for use [1].  The
    po4a-updatepo command has been replaced by the po4a command and are not used
    from anywhere.
    * po/doc/local.mk (%D%/%.pot): Use a po4a command instead of the po4a-updatepo
    for the POT generation.  This eliminates the warning of po4a-updatepo;
    "po4a-updatepo is deprecated.  The unified po4a(1) program is more convenient
    and less error prone."  Here, the file paths are passed using variables.  This
    is because the po4a command needs to be executed for each language and each
    file.  Dummy values are passed for those that are not needed to update the POT
    file.
    * po/doc/po4a.cfg: Add a po4a config file for the POT generation.  The po4a
    command requires a configulation file.
    
    [1] https://po4a.org/man/man7/po4a.7.php.en#lbAS
    
    Change-Id: Ica39a0d1f77b6a64d37c592ac2e693319443d3c5
    Signed-off-by: Florian Pelz <pelzflorian@pelzflorian.de>


The old manual as referred to in maintenance.git in
hydra/modules/sysadmin/web.scm was expected to build with the
guix/self.scm of old guix.git; it should not try to use po4a.cfg.

Current po4a also still includes the old po4a tools (po4a-updatepo and
po4a-translate) from before; they just are little maintained.

Regards,
Florian