Changes to Indicates that a Link Agent has sent a heartbeat

added the new mabl_desktop enum value to the request property distribution

removed the request property agent_configuration/branch

added the new optional request property agent_configuration/link_agent_update_channel

removed the request property agent_state/mablnet/carriers_by_router

added the new optional request property agent_state/mablnet/carriers

removed the request property capacity/os_warnings/items/message

added the new optional request property connection_status/additionalProperties/unreachable_seconds

added the new optional request property capacity/os_warnings/items/params

added the new optional request property capacity/supported_tunnels

added the new optional request property tunnels_on_host