[NotAFlightRisk]

Description

The docs say DBBACKUP_GPG_ALWAYS_TRUST stays off unless you turn it on. It's actually been on for everyone with DBBACKUP_GPG_RECIPIENT set, since the recipient line in settings.py assigns to GPG_ALWAYS_TRUST too - so False is ignored and backups get encrypted to keys GPG hasnt been told to trust.

It'll catch a few people out on upgrade though. If your recipient key isn't trusted in GPG and you never set the option, encrypted backups will start failing with "invalid recipient" until you trust the key or set it to True. I've put that in the changelog entry.

Checklist

Please update this checklist as you complete each item:

• Tests have been developed for bug fixes or new functionality.
• The changelog has been updated, if necessary.
• Documentation has been updated, if necessary.
• GitHub Issues closed by this PR have been linked.

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