Update sonobuoy version (#9485)

The latest version of sonobuoy is v0.56.11.
This updates the version to the latest.

As the file name, this makes it use certified-conformance mode
clearly for the latest version of sonobuoy.

tests/testcases/100_check-k8s-conformance.yml

 ---
 - hosts: kube_control_plane[0]
   vars:
-    sonobuoy_version: 0.20.0
+    sonobuoy_version: 0.56.11
     sonobuoy_arch: amd64
     sonobuoy_parallel: 30
     sonobuoy_path: /usr/local/bin/sonobuoy
-    sonobuoy_skip: 'Alpha|Disruptive|Feature|Flaky|Slow|Serial'
-    sonobuoy_mode: Quick
+    sonobuoy_mode: certified-conformance
 
   tasks:
   - name: Run sonobuoy
@@ -26,7 +25,7 @@
         copy: no
 
     - name: Run sonobuoy
-      command: "{{ sonobuoy_path }} run --mode {{ sonobuoy_mode }} --e2e-parallel {{ sonobuoy_parallel }} --e2e-skip {{ sonobuoy_skip }} --wait"
+      command: "{{ sonobuoy_path }} run --mode {{ sonobuoy_mode }} --e2e-parallel {{ sonobuoy_parallel }} --wait"
       when: sonobuoy_enabled | default(false)
 
     - name: Run sonobuoy retrieve
@@ -34,4 +33,4 @@
       register: sonobuoy_retrieve
 
     - name: Run inspect results
-      command: "{{ sonobuoy_path }} e2e {{ sonobuoy_retrieve.stdout }}"
+      command: "{{ sonobuoy_path }} results {{ sonobuoy_retrieve.stdout }} --plugin e2e --mode report"