Remove unnecessary failed_when (#7120)

TASK [Generate a list of information about the images on a node]
registers list of container images to docker_images.
Then the next TASK [Set pull_required if the desired image is not
yet loaded] does based on expecting images are registered.
However sometimes the first TASK was failed as [1] but the failure
is ignored due to failed_when:false and it makes another issue.
This removes this unnecessary failed_when to detect the failure
at the point.
In addition, this removes no_log:true also because the output doesn't
contain any sensitive data and now it just makes debugging difficult.

[1]: https://gitlab.com/kargo-ci/kubernetes-sigs-kubespray/-/jobs/934714534#L2953

roles/download/tasks/check_pull_required.yml

@@ -6,9 +6,7 @@
 # nginx:1.15,gcr.io/google-containers/kube-proxy:v1.14.1,gcr.io/google-containers/kube-proxy@sha256:44af2833c6cbd9a7fc2e9d2f5244a39dfd2e31ad91bf9d4b7d810678db738ee9,gcr.io/google-containers/kube-apiserver:v1.14.1,etc...
 - name: check_pull_required |  Generate a list of information about the images on a node  # noqa 305 image_info_command contains a pipe, therefore requiring shell
   shell: "{{ image_info_command }}"
-  no_log: true
   register: docker_images
-  failed_when: false
   changed_when: false
   check_mode: no
   when: not download_always_pull