Update ember-cli-babel to version 6.2.0 🚀

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Hello lovely humans,

ember-cli-babel just published its new version 6.2.0.

State	Update 🚀
Dependency	ember-cli-babel
New version	6.2.0
Type	dependency

This version is not covered by your current version range.

Without accepting this pull request your project will work just like it did before. There might be a bunch of new features, fixes and perf improvements that the maintainers worked on for you though.

I recommend you look into these changes and try to get onto the latest version of ember-cli-babel.
Given that you have a decent test suite, a passing build is a strong indicator that you can take advantage of these changes by merging the proposed change into your project. Otherwise this branch is a great starting point for you to work on the update.

Do you have any ideas how I could improve these pull requests? Did I report anything you think isn’t right?
Are you unsure about how things are supposed to work?

There is a collection of frequently asked questions and while I’m just a bot, there is a group of people who are happy to teach me new things. Let them know.

Good luck with your project ✨

You rock!

🌴

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The new version differs by 186 commits .

• 1286e54 Revert "[FIXES #150] update babel-preset-env"
• df2e98a release v6.2.0 🎉
• 346b53c [FIXES #150] update babel-preset-env
• 603667a Merge pull request #148 from babel/node-8
• 79a33cf allow node 8 to fail until ember-cli is updated
• 5b52b66 lock to older version of preset-env (before the breaking change)
• fb07e99 skip failed test
• 86260f4 skip test that is failing because babel-preset-env changed it API (will fix later)
• 6eb7285 [BUGFIX #147] add node 8 support
• 65038c7 Merge pull request #144 from babel/update
• b8e1107 upgrade all the deps
• aca5787 Merge pull request #139 from rwjblue/update-readme
• 718e419 Specifically call out the @glimmer/env import path.
• 7567ada Merge pull request #138 from babel/Turbo87-patch-1
• ffb7850 README: Add missing return type

There are 186 commits in total. See the full diff.