[22735] Make the machine id the physical data host info

[juanjo4936]

This PR modifies the info that gets fed into the fastdds.physical_data host element, the machine_id instead of the host_id as it was before.

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[cferreiragonz]

Looks great! Although I believe we should check if the machine-id is empty before using it to set the property, and fall back to the previous method in case it is empty. This might happens in certain docker environments.

[cferreiragonz]

LGTM with green CI