[Fixes #14318] Improve logging

[etj]

#14318

• improve log format
• add the missing recommended root logger
• remove the unused mail_admins handler
• remove the unused logstash and masptore2 loggers
• replace the deprecated alias WARN to WARNING

Checklist

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 74.90%. Comparing base (0495358) to head (1d781e1).
⚠️ Report is 4 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #14319      +/-   ##
==========================================
- Coverage   74.91%   74.90%   -0.01%     
==========================================
  Files         982      982              
  Lines       60496    60496              
  Branches     8247     8247              
==========================================
- Hits        45319    45317       -2     
- Misses      13346    13349       +3     
+ Partials     1831     1830       -1     

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[Copilot]

Pull request overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated no new comments.

Comments suppressed due to low confidence (1)

geonode/settings.py:682

• The importer logger is set to INFO but has no handler of its own; with the root logger set to WARNING, any INFO records from importer will be dropped when they propagate to root. Either raise the root level or attach the console handler directly to importer (and disable propagation) so the configured INFO level has effect.

        "importer": {
            "level": "INFO",
        },