Migrated tests to jest

Used jest-codemods to migrate, will have to pass everything by hand before we can merge.

test6/sortCharactersInString/sortCharactersInString.js

@@ -0,0 +1,2 @@
+const sortCharactersInString = str => [...str].sort((a, b) => a.localeCompare(b)).join('');
+module.exports = sortCharactersInString;

test6/sortCharactersInString/sortCharactersInString.test.js

@@ -0,0 +1,9 @@
+const expect = require('expect');
+const sortCharactersInString = require('./sortCharactersInString.js');
+
+test('Testing sortCharactersInString', () => {
+  //For more information on all the methods supported by tape
+  //Please go to https://github.com/substack/tape
+  expect(typeof sortCharactersInString === 'function').toBeTruthy();
+  expect(sortCharactersInString('cabbage')).toBe('aabbceg');
+});