feat(NODE-5197): add server monitoring mode

[durran]

Description

Introduces a new serverMonitoringMode flag to tell monitors to stream, poll, or auto-detect.

What is changing?

• Updates FaaS automated tests to assert that no awaited=true flags are set on the server heartbeat started events.
• Adds serverMonitoringMode (stream|poll|auto) to URI options and MongoClientOptions
• Updates monitor behaviour to poll or stream based on options or environment.
• Ensures dedicated connection is used for RTT pinging in polling mode.
• Updates Unified test runner to work with schema 1.17
• Syncs SDAM unified tests
• Syncs URI options tests

Is there new documentation needed for these changes?

Yes, we must document the new option.

What is the motivation for this change?

NODE-5197

Release Highlight

New client option serverMonitoringMode added.

For users that want to control the behaviour of the monitoring connection between each node in the topology, a new option, serverMonitoringMode, has been added. This defaults to auto but can be forced into a specific mode by providing a value of poll or stream. A polling monitor periodically issues a hello command to the node at an interval of heartbeatFrequencyMS. A streaming monitor sends an initial hello and then will automatically get a response from the Node when a change in server configuration occurs or at a maximum time of heartbeatFrequencyMS. The value of that option defaults to 10000 milliseconds.

This new option can be provided in the connection string or as an option to the MongoClient.

// In the connection string.
new MongoClient('mongodb://127.0.0.1:27017/?serverMonitoringMode=stream');

// In the options
new MongoClient('mongodb://127.0.0.1:27017/', { serverMonitoringMode: 'stream' });

Double check the following

• Ran npm run check:lint script
• Self-review completed using the steps outlined here
• PR title follows the correct format: type(NODE-xxxx)[!]: description
  • Example: feat(NODE-1234)!: rewriting everything in coffeescript
• Changes are covered by tests
• New TODOs have a related JIRA ticket