fix(NODE-4208): add aws http request timeout handler

[dariakp]

Description

NODE-4208

What is changing?

• Adding a new subclass of MongoRunTimeError: MongoAWSError (inspired by the analogous error class for Kerberos)
• Adding a handler for the http request timeout error for AWS requests
• Adding a new environment variable to the EC2 test suite so that the new integration test can run only in the EC2 environment (since the other AWS test suites have credentials already available without the http call)

Is there new documentation needed for these changes?

No

What is the motivation for this change?

Fixes a bug where the default specified timeout of 10000ms for aws http requests was not being respected.

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
• [N/A] New TODOs have a related JIRA ticket