Summary
We should extend our test coverage for the Amazon Linux 2 (ARM64) and CentOS 7 (x86_64) which line up with what Atlas is using. 

Motivation

• Does this affect any team outside of WT?
  (Are they blocked? Are they waiting for an answer?)

No.

• How likely is it that this use case or problem will occur?
  (Main path? Edge case? Frequency of the issue?)

N/A. It's a test coverage extension. 

• If the problem does occur, what are the consequences and how severe are they?
  (A minor annoyance at a log message? Performance concern? Outage/unavailability? Test Failure?)

N/A.

• Is this issue urgent?
  (Does this ticket have a required timeline? What is it?)

Important but not urgent.

Acceptance Criteria (Definition of Done)
(When will this ticket be considered done? What is the acceptance criteria for this ticket to be closed?)

• Testing
  (What all testing needs to be done as part of this ticket? Unit? Functional? Performance?Testing at MongoDB side?)

Have basic WT correctness test suites running against the 2 OS'es in WiredTiger (develop) Evergreen project.

• Documentation update
  (Does this ticket require a change in the architecture guide? If yes, please create a corresponding doc ticket.)

No.

[Optional] Suggested Solution
(Is there any suggested solution to handle this issue? Is it related to any existing WT ticket? Is it related to any previous issue fixed? If yes, link the WT ticket number using related to, depends on, dependent on by links)

The Ubuntu 18.04 build variant can be used as the baseline to craft test coverage for the 2 OS'es. Consider running tests for the 2 OS'es periodically (e.g. once per day) in mainline builds.