Update Linkwarden to version 2.9.3 and run as root

[al-lac]

Tested update on Umbrel Home and fresh install on Raspberry Pi 5.

I noticed some bugs like Linkwarden not being able to create snapshots of websites. This is due to the fact that official support for non-root is still missing.
There is already a PR open for non-root support: linkwarden/linkwarden#779

Also changed the database url as I have seem some errors in the logs. Changing it to the full name seems to fix it.

Would run it as root for the time being if that is ok @nmfretz

[github-actions]

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Linting Results

Severity	File	Description
ℹ️	linkwarden/docker-compose.yml	Potentially using unsafe user in service "postgres": The default container user "root" can lead to security vulnerabilities. If you are using the root user, please try to specify a different user (e.g. "1000:1000") in the compose file or try to set the UID/PUID and GID/PGID environment variables to 1000.
ℹ️	linkwarden/docker-compose.yml	Potentially using unsafe user in service "app": The default container user "root" can lead to security vulnerabilities. If you are using the root user, please try to specify a different user (e.g. "1000:1000") in the compose file or try to set the UID/PUID and GID/PGID environment variables to 1000.

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[nmfretz]

Excellent update @al-lac. Great find and fixes re the non-root user issue and postgres url.

Tested and working great.

Under our current apps framework we can run as root if necessary so as to not unnecessarily hamper an apps functionality.

Going from non-root to root user doesn't require us to handle any permissions issues luckily. When non-root support is live we'll need to handle permissions for users updating but not for fresh installs.