Store data in a nested object

[ASaiAnudeep]

Is your feature request related to a problem? Please describe.
update data under a existing data store key.

Describe the solution you'd like

await spec()
  .get('/users/1')
  .store('FIRST_USER', '.')

data in store

{ 'FIRST_USER': { id: '1', name: 'some name' } }

await spec()
  .get('/users/1/addresses')
  .store('FIRST_USER', 'addresses', '.')

updated data in store

{ 'FIRST_USER': { id: '1', name: 'some name', addresses: [ { zip: '12345' } ] } }