morpheus network add with option for TrunkOnly=on returning true instead

New VLAN Trunk option with morpheus networks should show TrunkOnly on or off

https://support.hpe.com/hpesc/public/docDisplay?docId=sd00008014en_us&page=GUID-1382CDA7-49B8-414C-A646-B363B27E3E0A.html

snip from Trunk created from UI

"config": {
"hvmTrunkOnly": "on",
"hvmVlanTrunks": "2500-2528"
}

snip from test creation from CLI

--option config.hvmTrunkOnly="on" \
--option config.hvmVlanTrunks="$trunk_list" \

snip from dry run --curl

"network": {
"config": {
"hvmTrunkOnly": true,
"hvmVlanTrunks": "2550-2600"
},

Reproduce the `morpheus network add` example with `config.hvmTrunkOnly="on"` and inspect the `--dry-run --curl` output. Compare it with the UI payload in the issue and trace the network-add option handling to identify where `on` becomes `true`. Done when the generated request represents `hvmTrunkOnly` as `on` or `off` consistently.

Written by the indexing model from the issue text.