add file and blob globals to eslint config

[shamilovtim]

Summary

The eslint community config does not have the File and Blob polyfills in globals which have been part of the Javascript implementation for ~3 years. They were added to the Javascript API in facebook#11573 by @satya164.

Changelog

[General] [Fixed] - Added File and Blob globals to eslint community config

Test Plan

Evidence these globals exist:

1. Implement Blob support for XMLHttpRequest facebook/react-native#11573
2. Executed the following:

3. Receive in console:

Evidence the PR works: the globals in the PR identical to the others in the eslint community config that they are in