fix(NODE-6864): socket errors are not always converted to MongoNetworkErrors

[nbbeeken]

Description

What is changing?

• Ensure socket errors are converted
• Do not squash error in finally block

Is there new documentation needed for these changes?

No

What is the motivation for this change?

Networking errors are handled specially for retry/resume logic, if we fail to wrap them in our Network error type we won't retry them.

Release Highlight

Network errors could have been left unwrapped in a MongoNetworkError

If the timing was perfectly unlucky a socket error event could store a plain Node.js error (like read ECONNRESET) on the connection class which would then be thrown unwrapped when cleaning up the failed socket read. This only was reproducible when the mongod node was killed with SIGKILL allowing for no time for a graceful socket shutdown.

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