fix: LEAP-1456: CSRF - use $http_host instead of nginx $host so port will be included

[jombooth]

host is just localhost when LSO is running in docker; http_host has the port number. If the port number isn't present in the result from get_host, this check will fail: https://github.com/django/django/blob/stable/4.2.x/django/middleware/csrf.py#L277-L288

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[TheAIWizard]

Hi,

I'm still encountering the 403 Forbidden error related to CSRF, mentioned in #6296, even after updating to version 1.14.0, which was supposed to address the CSRF errors when using Docker (#6344).

Could you please assist with resolving this?

Thanks in advance!