Missing instructions from upgrading MariaDB from 10.4 to 11.4

Issue in ./help/cloud-guide/services/services-yaml.md

According to the engineering team via support tickets, you cannot upgrade MariaDB directly from 10.4 to 11.4. Instead, you must upgrade from v10.4 -> v10.11 -> v11.4

The documentation does not specify this limitation / upgrade path.

I would recommend including this in the documentation on service upgrades.

Open help/cloud-guide/services/services-yaml.md and find the service-upgrade instructions. Read the surrounding guidance, then document that MariaDB cannot be upgraded directly from 10.4 to 11.4 and must follow the 10.4 → 10.11 → 11.4 path. Done means the documented upgrade sequence clearly includes this limitation.

Written by the indexing model from the issue text.