Ignore warnings when exporting a MobX observer component

[HorusGoul]

Like #51, the mobx-react-lite works with high order components to connect components to MobX stores.

See the docs: https://mobx.js.org/react-integration.html

Workaround
As a workaround, I patched the package to add observer to the reactHOCs list:

eslint-plugin-react-refresh/src/only-export-components.ts

Line 301 in ba9bb7b

const reactHOCs = new Set(["memo", "forwardRef"]);

Ideal solution
A way to configure additional HOCs.

[ArnaudBarre]

Seems like a legit usecase. Instead of adding it directly, I think a new option make sens here for others/future librairies with similar pattern.

I'll keep it in my backlog, but if you want to contribute, feel free to send a PR similar to https://github.com/ArnaudBarre/eslint-plugin-react-refresh/pull/55/files?w=1!