Update contract submodule

[patitonar]

Updated contract submodule to version 2.3.1

[netlify]

Deploy preview for kind-kilby-95344f processing.

Building with commit 0ca3248

https://app.netlify.com/sites/kind-kilby-95344f/deploys/5ce7ff5909a2470008ae3f5a

[coveralls]

Pull Request Test Coverage Report for Build 498

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 9.244%

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Totals
Change from base Build 488:	0.0%
Covered Lines:	122
Relevant Lines:	1436

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💛 - Coveralls

[akolotov]

Do you need update the env files to deploy contracts since 2.1.0 and 2.3.1 have different set of fields?

[akolotov]

@patitonar e2e testing fails in the TravisCI:

npm ERR! code ENOLOCAL
npm ERR! Could not install from "node_modules/web3-providers-ws/websocket@git:/github.com/frozeman/WebSocket-Node.git#6c72925e3f8aaaea8dc8450f97627e85263999f2" as it does not contain a package.json file.

[patitonar]

Thanks @akolotov I'm reviewing the issue, it seems that a dependency is having some issues to be fetched. It also affects the PR on the oracle

[akolotov]

Thanks @akolotov I'm reviewing the issue, it seems that a dependency is having some issues to be fetched. It also affects the PR on the oracle

Arsenii Petrovich reported yesterday about the same issue in his experiments. He solved it by removing package.json in the contracts repository.