feat: support bob.config.cjs for configuration (#442)

### Summary

I have a library configured with `"type": "module"`. This means that I
need to provide `bob.config.cjs`, as `.js` extensions won't do. That
config file needs to be explicitly added to the cosmicConfig

packages/react-native-builder-bob/src/index.ts

@@ -18,7 +18,7 @@ const { name, version } = require('../package.json');
 
 const root = process.cwd();
 const explorer = cosmiconfigSync(name, {
-  searchPlaces: ['package.json', `bob.config.js`],
+  searchPlaces: ['package.json', `bob.config.js`, 'bob.config.cjs'],
 });
 
 const FLOW_PRGAMA_REGEX = /\*?\s*@(flow)\b/m;