[fixes #11734] standing up docker compose stack on a port different than 80

[ricardogsilva]

This PR includes a small change to the nginx-related geonode.conf.envsubst file. It replaces usage of NGINX's $host variable with $http_host.

As mentioned in #11734, the $host variable does not preserve port information, which means that the current configuration does not allow the django service to know what was the original port from which outside requests came from - and therefore the GeoNode API is not able to generate correct URLs, which in turn means the UI is not functional.

This is really only a problem if the system maintainer wants to have GeoNode running on a port different from 80.

• Fixes standing up docker compose stack on a port different than 80 #11734

Checklist

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[codecov]

Codecov Report

Merging #11736 (1316622) into master (7cac111) will decrease coverage by 0.01%.
The diff coverage is n/a.

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #11736      +/-   ##
==========================================
- Coverage   62.97%   62.96%   -0.01%     
==========================================
  Files         875      875              
  Lines       52573    52573              
  Branches     6610     6610              
==========================================
- Hits        33107    33104       -3     
- Misses      17944    17946       +2     
- Partials     1522     1523       +1     

[ridoo]

This SO answer summarizes cases when $host and http_host are not the same:

This variable may have a different value from $http_host in such cases: 1) when the Host input header is absent or has an empty value, $host equals to the value of server_name directive; 2)when the value of Host contains port number, $host doesn't include that port number. $host's value is always lowercase since 0.8.17.

[ricardogsilva]

I'm not really sure why the codecov check is failing with a coverage drop of 0.01% as this PR only changes a configuration file in docker-related stuff - as far as I am aware there are no tests that would cover this. But please let me know if there is some additional action that I should take in this regard