TrigCost: Save the hostname to CostMetadata EDM

Save to hostname to the new cost EDM container TrigCostMetadataContainer and read it in Cost Processing. The example size of the new container is available in related ticket. The hostname is retrieved using the boost library boost::asio::ip::host_name().

The additional flag was added to Cost Processing --oksMetadata to retrieve details from OKS about the run (based on passed hostname).

The OKS reading will be added as the next step.

Size in BS after suggested changes:

---- xAOD::TrigCompositeContainer_v1#HLT_RuntimeMetadata, Size: 144 bytes
---- xAOD::TrigCompositeAuxContainer_v2#HLT_RuntimeMetadataAux., Size: 276 bytes
------ vector<string>#HLT_RuntimeMetadataAux.hostname, Size: 96 bytes

Related to: ATR-24424

Tagging @okuprash @tamartin