call_v2 cross-contract calls with additional limit parameters

[ascjones]

Requires version of pallet-contracts including call_v2 host function. Introduced in this commit

There is a new host function call_v2 which allows passing both Weight parts: ref_time_limit and proof_time_limit and the storage_deposit_limit. The legacy call function only provides the single gas_limit parameter, which is used as the value for ref_time_limit.

The call extrinsic already requires these, so this just brings the cross-contract call API into line with the extrinsic.

These parameters can be set on a call builder instance, e.g.

call_builder
  .ref_time_limit(ref_time_limit)
  .proof_time_limit(proof_time_limit)
  .storage_deposit_limit(storage_deposit_limit)
  .invoke();

Calling invoke will cause the host function ext::call_v2 to be invoked, with the supplied parameters.

To call the original call host function with just the gas_limit parameter, call the call_v1 method on the call builder:

call_builder
  .call_v1()
  .gas_limit(ref_time_limit)
  .invoke();

Calling invoke will cause the host function ext::call to be invoked, with the supplied parameters.

[SkymanOne]

LGTM. Need also to add migration notice in ink-docs

[ascjones]

One unrelated test currently failing, should be fixed in #2101