Flaky GKE tests

Problem

Some tests on GKE are very unreliable failing for different reasons. This impacts development and shipping of other features when testing on GKE. E.g.:

Sentry

Developing fluentd integration

https://gitlab.com/gitlab-org/cluster-integration/cluster-applications/-/jobs/506703763

FAILED RELEASES:
NAME
sentry
in /usr/local/share/gitlab-managed-apps/helmfile.yaml: in .helmfiles[5]: in sentry/helmfile.yaml: failed processing release sentry: helm exited with status 1:
  Error: Job failed: BackoffLimitExceeded

Developing Knative integration

https://gitlab.com/gitlab-org/cluster-integration/cluster-applications/-/jobs/506024938

FAILED RELEASES:
NAME
sentry
in /usr/local/share/gitlab-managed-apps/helmfile.yaml: in .helmfiles[5]: in sentry/helmfile.yaml: failed processing release sentry: helm exited with status 1:
  Error: timed out waiting for the condition

Cilium

Got stuck during the master branch pipeline after merging FluentD

https://gitlab.com/gitlab-org/cluster-integration/cluster-applications/-/jobs/506791243

Falco

Failed on master after updating the Runner image tag (completely unrelated). It passed after retrying

https://gitlab.com/gitlab-org/cluster-integration/cluster-applications/-/jobs/679554352

https://gitlab.com/gitlab-org/cluster-integration/cluster-applications/-/jobs/671081235

certmanager-no-issuer

https://gitlab.com/gitlab-org/cluster-integration/cluster-applications/-/jobs/692778366

Proposal

1. As a quick fix I suggest we comment the tests out.
2. Then open another MR to try to fix it.