(deps): upgrade to Jest 25

- upgrade jest, ts-jest, @types/jest, and jest-watch-typeahead

- Jest 25 changes exports so change internal import to handle properly

- Jest 25 drops support for Node <8 that doesn't impact us
  - we only support Node 10+ anyway
- Jest 25 upgrades JSDOM from v11 to v15, which is potentially breaking
  for any users that relied on some older behavior

- yarn.lock changed heavily
  - from a look-over, many are from babel-jest (which is included with
    Jest) upgrading its Babel deps, some from istanbul for coverage,
    and lots of other transitive deps I can't really tell from a glance

README.md

@@ -465,7 +465,7 @@ Examples
 
 ### `tsdx test`
 
-This runs Jest v24.x, forwarding all CLI flags to it. See [https://jestjs.io](https://jestjs.io) for options. For example, if you would like to run in watch mode, you can run `tsdx test --watch`. So you could set up your `package.json` `scripts` like:
+This runs Jest, forwarding all CLI flags to it. See [https://jestjs.io](https://jestjs.io) for options. For example, if you would like to run in watch mode, you can run `tsdx test --watch`. So you could set up your `package.json` `scripts` like:
 
 ```json
 {

package.json

@@ -53,7 +53,7 @@
     "@rollup/plugin-json": "^4.0.0",
     "@rollup/plugin-node-resolve": "^7.1.0",
     "@rollup/plugin-replace": "^2.2.1",
-    "@types/jest": "^24.0.15",
+    "@types/jest": "^25.2.1",
     "@typescript-eslint/eslint-plugin": "^2.12.0",
     "@typescript-eslint/parser": "^2.12.0",
     "ansi-escapes": "^4.2.1",
@@ -80,8 +80,8 @@
     "eslint-plugin-react-hooks": "^2.2.0",
     "execa": "4.0.0",
     "fs-extra": "^9.0.0",
-    "jest": "^24.8.0",
-    "jest-watch-typeahead": "^0.4.0",
+    "jest": "^25.3.0",
+    "jest-watch-typeahead": "^0.5.0",
     "jpjs": "^1.2.1",
     "lodash.merge": "^4.6.2",
     "ora": "^4.0.3",
@@ -97,7 +97,7 @@
     "semver": "^7.1.1",
     "shelljs": "^0.8.3",
     "tiny-glob": "^0.2.6",
-    "ts-jest": "^24.0.2",
+    "ts-jest": "^25.3.1",
     "tslib": "^1.9.3",
     "typescript": "^3.7.3"
   },

src/index.ts

@@ -13,7 +13,7 @@ import {
 import asyncro from 'asyncro';
 import chalk from 'chalk';
 import * as fs from 'fs-extra';
-import jest from 'jest';
+import * as jest from 'jest';
 import { CLIEngine } from 'eslint';
 import logError from './logError';
 import path from 'path';