Multichain Provider

[alexcos20]

(part of oceanprotocol/pm#185)

Make sure that chainId is available when provider cannot figure it out.
Provider will choose the corresponding web3 object based on chainId

This affects code in https://github.com/oceanprotocol/ocean.js/blob/main/src/services/Provider.ts.

Provider calls that need to be updated:

• /api/services/encrypt - add chainId , in case Provider has different privateKeys per each chain

Provider calls that do not need updates:

• /api/services/initialize - no need, provider will take chainId by resolving DID

• /api/services/download - no need, provider will take chainId by resolving DID

• /api/services/fileinfo - no need, provider will take chainId by resolving DID if DID is passed, otherwise it's just a Files object

• POST /api/services/compute - - no need, provider will take chainId by resolving each DID (algo, datasets, etc)

• Add integration tests for the multichain provider

• By using this barge branch: add multichain provider in addition to existing providers barge#348 let's add a test for publish the asset, edit the metadata service and then consume the asset.