fix(lambda): flaky test due to terminal instance

[vicheey]

Problem

fix #6913

Solution

Move the spy instantiation closer to reduce side effects. Add delay before start running command so additional for clean up to reduce chance of flakiness. Change assertion from true/false to count comparison to give more info for debugging in case the flakiness persists into the future.

---

• Treat all work as PUBLIC. Private feature/x branches will not be squash-merged at release time.
• Your code changes must meet the guidelines in CONTRIBUTING.md.
• License: I confirm that my contribution is made under the terms of the Apache 2.0 license.

[github-actions]

• This pull request implements a feat or fix, so it must include a changelog entry (unless the fix is for an unreleased feature). Review the changelog guidelines.
  • Note: beta or "experiment" features that have active users should announce fixes in the changelog.
  • If this is not a feature or fix, use an appropriate type from the title guidelines. For example, telemetry-only changes should use the telemetry type.

[Hweinstock]

What is the race condition? Could it affect users or is it test specific?