Update Mattermost to v10.2.1

[al-lac]

Tested on Raspberry Pi 5

[github-actions]

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Linting Results

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
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ℹ️	Info: This is just for your information.