Hardhat v2.17.1

This release adds support for solc v0.8.21, allows using console.log in pure functions and improves the output of the flatten task (see #1499).

Besides that, this version:

• Removed an unnecessary dependency (abort-controller) because it's no longer needed in the versions of node.js supported by Hardhat (thanks @orlandoortegajr!)
• Fixed a bug caused by nodes returning 429 responses without a Retry-After header (thanks @kowalski!)
• Added logic to throw an error when the debug_traceTransaction method is called with a tracer parameter that is not supported.