Migrated tests to jest

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

test/pullBy/pullBy.js

@@ -1,10 +0,0 @@
-const pullBy = (arr, ...args) => {
-const length = args.length;
-let fn = length > 1 ? args[length - 1] : undefined;
-fn = typeof fn == 'function' ? (args.pop(), fn) : undefined;
-let argState = (Array.isArray(args[0]) ? args[0] : args).map(val => fn(val));
-let pulled = arr.filter((v, i) => !argState.includes(fn(v)));
-arr.length = 0;
-pulled.forEach(v => arr.push(v));
-};
-module.exports = pullBy;