Update chai to version 4.0.0 🚀

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Hello lovely humans,

chai just published its new version 4.0.0.

State	Update 🚀
Dependency	chai
New version	4.0.0
Type	devDependency

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 chai.
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 430 commits .

• ab1fbad Merge pull request #973 from chaijs/chore-uncomment-travis-deploy
• 545ca2f chore: uncomment travis lines
• 6349ff4 Merge pull request #972 from lucasfcosta/release-4.0.0
• 0fe98b1 chai@4.0.0
• 30a4451 Merge pull request #967 from lucasfcosta/remove-lib-bump
• 8ba95a7 Remove bump command to change lib/chai.js
• 0825826 Merge pull request #964 from zetamorph/assert-nestedInclude-ownInclude
• f3adfd9 fix: PhantomJS 1.x incompatibility (#966)
• b744130 Assert: made documentation more descriptive
• 33e4403 test: added custom message test to negated .nested-, .deep-, .own.include
• 4180242 test: added message argument to negated nested-, deep-, own- and deepOwnInclude
• 40bb490 assert interface: add .deepOwnInclude and notdeepOwnInclude
• 97b6243 assert interface: add .ownInclude and .notOwnInclude
• 24d7fa3 assert interface: add deepNestedInclude and notDeepNestedInclude
• 7063b94 assert interface: add nestedInclude and notNestedInclude

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