Fix race condition with config in asset uploader

Author: amazon-meaisiah

lambdas/static-asset-uploader/index.js

@@ -265,6 +265,8 @@ class State {
       klaw('./build')
         .on('data', (data) => {
           if (data.stats.isDirectory()) return
+          // skip config - we generate that later
+          if (!/build\/config\.js$/.test(data.path)) return
           if (this.event.RequestType === 'Create') {
             // always write everything on Creates
             console.log('pushing b/c Create', data.path)