test(ec2): unreliable test "SSH Agent can start the agent on windows"

Problem:

    SSH Agent
      can start the agent on windows:
      Error: Test length exceeded max duration: 30 seconds
    [No Pending UI Elements Found]
      at Timeout._onTimeout (D:\a\aws-toolkit-vscode\aws-toolkit-vscode\packages\core\src\test\setupUtil.ts:46:32)

Solution:
- retry 2 times.
- set short timeout.

Author: justinmk3

packages/core/src/test/shared/extensions/ssh.test.ts

@@ -15,6 +15,9 @@ import { isWin } from '../../../shared/vscode/env'
 
 describe('SSH Agent', function () {
     it('can start the agent on windows', async function () {
+        this.timeout(10000)
+        this.retries(2)
+
         // TODO: we should also skip this test if not running in CI
         // Local machines probably won't have admin permissions in the spawned processes
         if (process.platform !== 'win32') {