The ESLint config for the extension explicitly includes support for
Prettier. However, this is already being provided by our global ESLint
config (`@metamask/eslint-config`). Therefore there is no need to
include it here. In fact, this is causing weird issues where the `curly`
option is getting overridden somehow. After this change, these syntaxes
are invalid:
``` javascript
if (foo) return;
```
``` javascript
if (foo) return 'bar';
```
