test(flaky): fix unresolved promise causing linux failures (#6088)

## Problem
#6043
To reproduce, add a 5 second delay to the `after` hook at the top level.
One way to do this is to insert this at line 84. 
``` 
after(async function () {
        clock.uninstall()
        await sleep(5000)
    })
```
Despite asserting that the promise rejects within the test, the promise
rejects after the test as well. Not entirely sure why this happening.
- Tried manually wrapping in try-catch with an `await` instead of
`assert.rejects` and it still fails.
- Tried wrapping the promise in another promise before passing to
`assert.rejects`.

## Solution
What does appear to work, is manually handling the callback of the
promise. That is, explicitly defining a `then` and `catch` method to
assert the rejection, and awaiting the promise at the end of the test to
ensure it resolves before the test finishes. Not sure why this works,
but I am unable to reproduce the error with this change.

## Notes
- `assert.rejects` implementation:
https://github.com/nodejs/node/blob/3178a762d6a2b1a37b74f02266eea0f3d86603be/lib/assert.js#L653.
Doesn't appear to be the problem because the same is observed when
manually wrapping.
- `await` docs:
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/await




---

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License: I confirm that my contribution is made under the terms of the
Apache 2.0 license.

Author: Hweinstock

buildspec/shared/common.sh

@@ -8,7 +8,7 @@
 #   - "waiting for browser": from `ssoAccessTokenProvider.test.ts`, unclear how to fix it.
 #   - "HTTPError: Response code …": caused by github rate-limiting.
 #   - "npm WARN deprecated querystring": transitive dep of aws sdk v2 (check `npm ls querystring`), so that's blocked until we migrate to v3.
-_ignore_pat='Timed-out waiting for browser login flow\|HTTPError: Response code 403\|HTTPError: Response code 404\|npm WARN deprecated querystring\|npm WARN deprecated'
+_ignore_pat='HTTPError: Response code 403\|HTTPError: Response code 404\|npm WARN deprecated querystring\|npm WARN deprecated'
 
 # Do not print (noisy) lines matching these patterns.
 #   - "ERROR:bus… Failed to connect to the bus": noise related to "xvfb". https://github.com/cypress-io/cypress/issues/19299

packages/core/src/test/credentials/sso/ssoAccessTokenProvider.test.ts

@@ -310,27 +310,29 @@ describe('SsoAccessTokenProvider', function () {
         })
 
         it('respects the device authorization expiration time', async function () {
-            // XXX: Don't know how to fix this "unhandled rejection" caused by this test:
-            //      rejected promise not handled within 1 second: Error: Timed-out waiting for browser login flow to complete
-            //          at poll (…/src/auth/sso/ssoAccessTokenProvider.ts:251:15)
-            //          at async SsoAccessTokenProvider.authorize (…/src/auth/sso/ssoAccessTokenProvider.ts:188:23)
-            //          at async SsoAccessTokenProvider.runFlow (…/src/auth/sso/ssoAccessTokenProvider.ts:113:20)
-            //          at async SsoAccessTokenProvider.createToken (…/src/auth/sso/ssoAccessTokenProvider.ts:102:24)
-
             setupFlow()
             stubOpen()
             const exception = new AuthorizationPendingException({ message: '', $metadata: {} })
             const authorization = createAuthorization(1000)
             oidcClient.createToken.rejects(exception)
             oidcClient.startDeviceAuthorization.resolves(authorization)
 
-            const resp = sut.createToken()
+            const resp = sut
+                .createToken()
+                .then(() => assert.fail('Should not resolve'))
+                .catch((e) => {
+                    assert.ok(
+                        e instanceof ToolkitError &&
+                            e.message === 'Timed-out waiting for browser login flow to complete'
+                    )
+                })
+
             const progress = await getTestWindow().waitForMessage(/login page opened/i)
             await clock.tickAsync(750)
             assert.ok(progress.visible)
             await clock.tickAsync(750)
             assert.ok(!progress.visible)
-            await assert.rejects(resp, ToolkitError)
+            await resp
             assertTelemetry('aws_loginWithBrowser', {
                 result: 'Failed',
                 isReAuth: undefined,