Use central predefined 4096 bit DH params file (from Mozilla https://ssl-config.mozilla.org/ffdhe4096.txt ) instead of creation one via openssl command to speed up the installation. Thank you to @ahrasis for code suggestions.

Merge branch '6393-websites-php-version-gets-accidentally-altered-by-admin-if-websites-php-version-is-client_id-0' into 'develop'

Resolve "Websites php version gets (accidentally) altered by admin if websites php version is client_id != 0"

Closes #6393

See merge request ispconfig/ispconfig3!1657

Fix issue that PHP version of a site gets altered when an admin edits the site when domain limit mode is active.

Resolve "Add support for RHEL 9 and compatible clones"

Closes #6373

See merge request ispconfig/ispconfig3!1656

Match conversion from strftime to date got php 8

See merge request ispconfig/ispconfig3!1652

Fix undefined variable firewall_server_enabled and xmpp_server_enabled, #6400

See merge request ispconfig/ispconfig3!1653

Fix undefined $postfix_version and generalize code, #6405

Closes #6405

See merge request ispconfig/ispconfig3!1654

Fix undefined $conf, #6406

Closes #6406

See merge request ispconfig/ispconfig3!1655

Fixed Wrong DNS Validation #6357

See merge request ispconfig/ispconfig3!1616

Added validator for listname Fix #6362

Closes #6362

See merge request ispconfig/ispconfig3!1617

Collected minor correction/ translation fixes

See merge request ispconfig/ispconfig3!1646

Add content name to page title for edit forms, #6401

Closes #6401

See merge request ispconfig/ispconfig3!1648

Merge branch '6313-add-warning-to-update-script-when-incorrect-php-version-is-used-as-default' into 'develop'

Resolve "Add warning to update script when incorrect PHP version is used as default"

Closes #6313

See merge request ispconfig/ispconfig3!1647

Resolve "PHP warnings in Installer on PHP 8.1"

Closes #6398

See merge request ispconfig/ispconfig3!1643

Fix apps vhost tpl symlink

See merge request ispconfig/ispconfig3!1642

Source /etc/profile from cron.sh

See merge request ispconfig/ispconfig3!1640

Resolve "apps vhost template file error in dev"

Closes #6397

See merge request ispconfig/ispconfig3!1641