Update uglify-js to version 3.0.9 🚀

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Hello lovely humans,

uglify-js just published its new version 3.0.9.

State	Update 🚀
Dependency	uglify-js
New version	3.0.9
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 uglify-js.
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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GitHub Release

 

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The new version differs by 320 commits .

• 3408fc9 v3.0.9
• eae2675 introduce unsafe_regexp (#1970)
• 43add94 v3.0.8
• efcf167 make expect_stdout node version specific (#1963)
• 6ed9091 fix docs for side_effects flag to reflect current behavior (#1966)
• 569c21e improve RegExp handling (#1959)
• 87c3a2c remove space_colon (#1960)
• baef8bf update output options in readme (#1958)
• 0813c53 remove Travis CI badge
• c881394 v3.0.7
• cb45886 export TreeTransformer (#1950)
• 050474a v3.0.6
• f6c805a print package name alongside version in CLI (#1946)
• 9464d3c fix parsing of property access after new line (#1944)
• f18abd1 minor fixes to README.md

There are 250 commits in total. See the full diff.