test(NODE-4165): sync maxConnecting spec tests and update runner

[dariakp]

Description

NODE-4165

What is changing?

• Synced maxConnecting tests including changes from NODE-4165, NODE-3666, and NODE-2983.
• CMAP unit tests now run as integration tests, the maxConnecting tests are skipped for now, but they can be seen failing in a uniform manner here
• The runner has been updated with new TypeScript types for integration tests and also has a new ready operation, which is a no-op until pool pausing is implemented (no need for TODO, since the new tests for pool pausing will fail if this continues to be a no-op, and it does not play any role in the current tests)

Is there new documentation needed for these changes?

No

What is the motivation for this change?

Paving the way for the maxConnecting feature

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>
• Changes are covered by tests
• New TODOs have a related JIRA ticket

[baileympearson]

requesting changes for visibility but I really only have a couple questions.

[nbbeeken]

What do you think about using the test names like so?

[nbbeeken]

Discussed offline we can address cleanups in follow up