Update syncthing to version v1.27.9

[nmfretz]

This is an automated pull request to update syncthing to version v1.27.9. This PR must be reviewed and tested before merging.

[github-actions]

🎉   Linting finished with no errors or warnings   🎉

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Linting Results

Severity	File	Description
ℹ️	syncthing/docker-compose.yml	External port mapping "22000:22000/tcp": Port mappings may be unnecessary for the app to function correctly. Docker's internal DNS resolves container names to IP addresses within the same network. External access to the web interface is handled by the app_proxy container. Port mappings are only needed if external access is required to a port not proxied by the app_proxy, or if an app needs to expose multiple ports for its functionality (e.g., DHCP, DNS, P2P, etc.).
ℹ️	syncthing/docker-compose.yml	External port mapping "22000:22000/udp": Port mappings may be unnecessary for the app to function correctly. Docker's internal DNS resolves container names to IP addresses within the same network. External access to the web interface is handled by the app_proxy container. Port mappings are only needed if external access is required to a port not proxied by the app_proxy, or if an app needs to expose multiple ports for its functionality (e.g., DHCP, DNS, P2P, etc.).

Legend

Symbol	Description
❌	Error: This must be resolved before this PR can be merged.
⚠️	Warning: This is highly encouraged to be resolved, but is not strictly mandatory.
ℹ️	Info: This is just for your information.

[nmfretz]

Reviewed and tested