Add ESLint and Prettier tooling

__tests__/github.test.ts

@@ -1,7 +1,7 @@
-import { github } from '../src/github';
+import {github} from '../src/github'
 
 describe('@actions/github', () => {
   it('needs tests', () => {
-      expect(github()).toBe(true)
-  });
-});
+    expect(github()).toBe(true)
+  })
+})