GitLab

* Add FORWARDED_FOR_HEADERS to the reverse-proxy config
Signed-off-by: Dominic Giebert <dominic.giebert@suse.com>

* Add FORWARDED_FOR_HEADERS to documentation
Signed-off-by: Dominic Giebert <dominic.giebert@suse.com>

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Signed-off-by: Dominic Giebert <dominic.giebert@suse.com>