Merge remote-tracking branch 'main/stable-3.1' into dns_import

.git-scripts/syntax.sh

.gitlab-ci.yml

.phplint.yml

install/sql/README.txt

install/sql/incremental/upd_dev_collection.sql

install/sql/ispconfig3.sql

interface/web/admin/form/remote_user.tform.php

interface/web/admin/form/server_config.tform.php

interface/web/admin/form/users.tform.php

interface/web/admin/lib/lang/ar_remote_user.lng

interface/web/admin/lib/lang/ar_server_config.lng

interface/web/admin/lib/lang/ar_users.lng

interface/web/admin/lib/lang/bg_remote_user.lng

interface/web/admin/lib/lang/bg_server_config.lng

interface/web/admin/lib/lang/bg_users.lng

interface/web/admin/lib/lang/br_remote_user.lng

interface/web/admin/lib/lang/br_server_config.lng

interface/web/admin/lib/lang/br_users.lng

interface/web/admin/lib/lang/ca_remote_user.lng

interface/web/admin/lib/lang/ca_server_config.lng