Error: bad setState() call inside FileControl and EntryCard

**Describe the bug**

When accessing an editor with an image widget, this error is logged to the console, the first time an asset is accessed:

```
hook.js:608 Warning: Cannot update a component (`Connect(_translate)`) while rendering a different component (`FileControl`). To locate the bad setState() call inside `FileControl`, follow the stack trace as described in https://reactjs.org/link/setstate-in-render Error Component Stack
at FileControl (withFileControl.js:241:7)
at Widget (Widget.js:21:5)
...
```

The same thing happens in `EntryCard`, when a preview image is requested for the first time.

**To Reproduce**

* Checkout the decap-cms repo
* Install dependencies and run `npm start`
* Open http://localhost:8080/#/collections/kitchenSink/entries/a-big-entry-with-all-the-things
* Look into the console

**How to fix**

I have a fix ready for this and will submit a PR.