www/ilias: Update version 5.4.25=>7.7

Release 5.4.X branch has reached EOL. See:
https://docu.ilias.de/goto.php?target=wiki_1357_Release_5.4

Although 7.7 is a recent release yet it does not support php80 but as
mentioned here:
https://docu.ilias.de/goto.php?target=wiki_1357_Required_and_Supported_Software_ILIAS_7

The Technical Board intends to re-evaluate the max. supported PHP
version in ~August/September in regards to PHP 8. We'd predict a
positive impact on the code quality, if ILIAS developers could rely on
PHP >= 7.3 features.

Either way ilias 8 is supposed to be released with php 8 support
sometimes in August/September before the support for php 7.4 ends.

PR: 261610
Approved by: wen (maintainer-timeout)
Relnotes:
https://docu.ilias.de/goto.php?target=lm_1719&client_id=docu&lang=en