[change] Remove jest preset

Also add node-based unit tests for SSR APIs.

scripts/jest/config.node.js

@@ -0,0 +1,19 @@
+'use strict';
+
+module.exports = {
+  coveragePathIgnorePatterns: ['/node_modules/', '<rootDir>/packages/react-native-web/src/vendor/'],
+  modulePathIgnorePatterns: [
+    '<rootDir>/packages/benchmarks/',
+    '<rootDir>/packages/docs/',
+    '<rootDir>/packages/examples/',
+    '<rootDir>/packages/react-native-web/dist/'
+  ],
+  rootDir: process.cwd(),
+  roots: ['<rootDir>/packages'],
+  snapshotFormat: {
+    printBasicPrototype: false
+  },
+  testEnvironment: 'node',
+  testMatch: ['**/__tests__/**/?(*-)+(spec|test).node.[jt]s?(x)'],
+  timers: 'fake'
+};