Enable corejs option for core bundle bin-prettier.js and third-party.js

[fisker]

this PR requires #6866 , fixes #6891 , I tried to make a test for it, but failed. local test

before

$ cat index.js | node node_modules/prettier/bin-prettier --stdin --parser babel
[error] regeneratorRuntime is not defined

after

$ cat index.js | node dist/bin-prettier --stdin --parser babel
"use strict";

module.exports = require("./src/index");

diff

npm notice
-npm notice package: prettier@1.19.0
+npm notice package: prettier@1.20.0-dev
npm notice === Tarball Contents ===
npm notice 468B    package.json
-npm notice 1.4MB   bin-prettier.js
+npm notice 1.6MB   bin-prettier.js
npm notice 70.6kB  doc.js
npm notice 1.3MB   index.js
npm notice 1.1kB   LICENSE
npm notice 57.4kB  parser-angular.js
npm notice 266.2kB parser-babylon.js
npm notice 1.5MB   parser-flow.js
npm notice 139.6kB parser-glimmer.js
npm notice 51.4kB  parser-graphql.js
npm notice 110.7kB parser-html.js
npm notice 241.1kB parser-markdown.js
npm notice 351.8kB parser-postcss.js
npm notice 2.6MB   parser-typescript.js
npm notice 167.7kB parser-yaml.js
npm notice 3.7kB   README.md
npm notice 1.1MB   standalone.js
-npm notice 146.7kB third-party.js
+npm notice 296.0kB third-party.js
npm notice === Tarball Details ===
npm notice name:          prettier
-npm notice version:       1.19.0
+npm notice version:       1.20.0-dev
-npm notice filename:      prettier-1.19.0.tgz
+npm notice filename:      prettier-1.20.0-dev.tgz
-npm notice package size:  2.2 MB
+npm notice package size:  2.3 MB
-npm notice unpacked size: 9.6 MB
+npm notice unpacked size: 9.9 MB
-npm notice shasum:        0a355225fa968b1a716739508f2689d18a0a513a
+npm notice shasum:        5dc617bfb5759264b838f9d34d238578b220a850
-npm notice integrity:     sha512-p32VAB78i7JQT[...]txg82TWSxTi1A==
+npm notice integrity:     sha512-DLkijM5TPo6uU[...]PoR2Dnm5WbNGw==
npm notice total files:   18
npm notice
-prettier-1.19.0.tgz
+prettier-1.20.0-dev.tgz

• I’ve added tests to confirm my change works.
• (If changing the API or CLI) I’ve documented the changes I’ve made (in the docs/ directory)
• (If the change is user-facing) I’ve added my changes to changelog_unreleased/*/pr-XXXX.md file following changelog_unreleased/TEMPLATE.md.
• I’ve read the contributing guidelines.

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[lydell]

As far as I understand, we won’t need this in 2.0 so I’m closing. Let me know if I’ve misunderstood anything.

Closing in favor of #6894.