Update mongoose to version 4.9.7 🚀

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Hello lovely humans,

mongoose just published its new version 4.9.7.

State	Update 🚀
Dependency	mongoose
New version	4.9.7
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 mongoose.
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 1372 commits .

• d29a115 chore: release 4.9.7
• 1b2d1cd test: fix #5190 tests for < 3.4
• 773639a fix(model): handle Decimal type in insertMany correctly
• 958bbb2 test(model): repro #5190
• 4771b05 fix(schema): ensure correct path for deeply nested schema indexes
• f204aa7 test(schema): repro #5199
• e432de2 fix(schema): make remove a reserved name
• baedc21 style: fix lint
• 60920b9 Merge branch 'master' of github.com:Automattic/mongoose
• 9966920 fix(validation): handle returning a promise with isAsync: true
• 4cc2a55 test: repro #5171
• 01f3019 Merge pull request #5204 from phutchins/internalDocumentationFix
• 15809df docs: add details about unique not being a validator
• ee4584d Updating documentation to not be contradictory
• 908d209 fix: upgrade kareem to handle async pre hooks correctly

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