Add hook to GetRateLimit

[Baliedge]

This PR implements a generalized hook into rate limit hits by providing a unidirectional channel to receive request/response data. The initial use case is to implement Prometheus metrics to monitor status of high value rate limit name/key pairs.

The user will populate Config.EventChannel with a channel and implement goroutine(s) to read from the channel. An event is triggered when a rate limit hit is applied at its owner peer and request/response structures are sent to the channel.

This is intended to work for all peering behaviors: batching, non-batching, and global.

Other auxiliary changes:

• Upgrade golangci-lint to latest.
• Update GitHub Actions in workflows.
• Remove redundant call to golangci-lint in on-pull-request workflow.
• cluster.StartWith() extended with options arguments to add support for EventChannel.

[thrawn01]

LGTM! I'm assuming you are trying to track down a customer who is abusing the system?