Remove creation of unresolved discussion on failure

What does this MR do?

Base on the feedback we have received on posting a blocking alert on e2e test failures, it is causing reduction in developer productivity due to the noise/disturbance created on flaky tests that are unrelated.

Until we have a better solution (being discussed in gitlab-org/quality/quality-engineering/team-tasks#1804), we are going to disable alert comments.

Check-list

• Verify the change in all affected pipelines.