Blueprint 4

[jgoz]

Description

Upgrades the Blueprint dependencies in the web-console to v4:

• Upgrade guide: https://github.com/palantir/blueprint/wiki/Blueprint-4.0
• Docs: https://blueprintjs.com/docs/

The process for upgrading was recorded and documented here:
https://www.youtube.com/watch?v=Ew8BgdCfMDg

After the recording, I also did the following:

• Update licenses
• Update unit test snapshots
• Update selectors in e2e tests to use .bp4

Note that a webpack alias was needed to allow color variables to be overwritten. The reasoning is documented in webpack.config.js.

This PR has:

• been self-reviewed.
• added documentation for new or modified features or behaviors.
• added or updated version, license, or notice information in licenses.yaml
• added comments explaining the "why" and the intent of the code wherever would not be obvious for an unfamiliar reader.
• added unit tests or modified existing tests to cover new code paths, ensuring the threshold for code coverage is met.
• been tested in a test Druid cluster.

[vogievetsky]

Looks great!