[SAC] [OSGeo] #2975: update gitea configuration

[OSGeo]

#2975: update gitea configuration
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 Reporter:  strk           |      Owner:  sac@…
     Type:  task           |     Status:  new
 Priority:  normal         |  Milestone:  Unplanned
Component:  Systems Admin  |   Keywords:
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 From https://git.osgeo.org/gitea/admin:

 Deprecated config option `[mailer]` `HOST` present. Use `[mailer]`
 `SMTP_ADDR` instead. This fallback will be/has been removed in v1.19.0
 (and 1 more)
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Ticket URL: <https://trac.osgeo.org/osgeo/ticket/2975>
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