Update cm-data-subscriptions model

- rename leaf-list subscribers to subscriptionIds
- code using the same also updated
- not creating a new version of model as nobody is using it at the
  moment

Issue-ID: CPS-2088
Change-Id: I43d679047bdfc665b56f262757acc4bbaba2733f
Signed-off-by: mpriyank <priyank.maheshwari@est.tech>
6 files changed