chore: setup jest for use with Typescript tests

[karrui]

This PR adds the ability to run Typescript tests with Jest. All tests with file names that match

**/?(*.)+(spec|test).[t]s?(x)

will be run with Jest.

This PR also migrates a few tests to Typescript to check if ts-jest is working.

Features:

• A small lint improvement has been made to the autosorting and autogrouping of imports.
• Typescript tests are now ran with Jest.
• Update tsconfig.json to now allow for absolute imports: ../../../../../<root>/some/path -> src/some/path
• Add jest-mongodb-config. With this, we can eventually stop using npm run download-binary and delete tests/end-to-end/helpers/get-mongo-binary.js since the config automatically retrieves that information for us.

New scripts:

• Add test-backend-jest script to run jest tests
• test-backend script now runs both jasmine and jest tests. Jasmine tests will be run first, followed by jest tests. Eventually, all tests will be written in Jest and Jasmine tests can be deleted.

[karrui]

Drafting this, I want to explore using Jest's automatic mongodb setup.

[karrui]

Ready for review. I think tests can be written in Typescript moving forward :)

[liangyuanruo]

largely lgtm! can i confirm the way to have jest run the tests instead of jasmine, is to convert them to TypeScript?

[karrui]

Yes. But also need to change all Jasmine usages to jest, and update the imports also