fix: include mocks in ignore config (#58)

# Summary

Hi there

My goal is ignoring __mocks__ folder  during the build

![image](https://user-images.githubusercontent.com/12049854/84309668-d1859e00-ab36-11ea-9f32-537ceb3f03a6.png)


## Test Plan

<!-- Demonstrate the code is solid. Example: The exact commands you ran and their output, screenshots / videos if the pull request changes UI. -->

### What's required for testing (prerequisites)?
nothing

### What are the steps to reproduce (after prerequisites)?
nothing

Author: alanhr

src/utils/compile.ts

@@ -27,7 +27,7 @@ export default async function compile({
     cwd: source,
     absolute: true,
     nodir: true,
-    ignore: '**/{__tests__,__fixtures__}/**',
+    ignore: '**/{__tests__,__fixtures__,__mocks__}/**',
   });
 
   report.info(