Update mattermost to v10.2.0

[al-lac]

Tested on Raspberry Pi 5.

[github-actions[bot]]

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Severity	File	Description
ℹ️	mattermost/docker-compose.yml	External port mapping "8443:8443/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	mattermost/docker-compose.yml	External port mapping "8443:8443/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]

Wonderful, thanks for this update @al-lac, it is working great! Sorry for the delay in reviewing while we had our heads down on the recent beta launch.

FYI, I added an extra newline in the release notes so they render like this: