Update React tutorial

[aefhm]

SUMMARY

We received some requests for a demo or example with React. We have a minimal example here. Let's test/confirm and then highlight it in our documentation.

Note. I think https://github.com/oasisprotocol/demo-oasisswag is the only demo we have that utilizes React, but unfortunately does not wrap Ethers or other ETH calls.

ISSUE TYPE

• Feature Idea

COMPONENT NAME

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