Remove s390X (#4063)

Signed-off-by: ShutingZhao <shuting@nirmata.com>

.krew.yaml

@@ -17,17 +17,6 @@ spec:
         - from: LICENSE
           to: .
       bin: kyverno
-    - selector:
-        matchLabels:
-          os: linux
-          arch: s390x
-      {{addURIAndSha "https://github.com/kyverno/kyverno/releases/download/{{ .TagName }}/kyverno-cli_{{ .TagName }}_linux_s390x.tar.gz" .TagName | indent 6 }}
-      files:
-        - from: kyverno
-          to: .
-        - from: LICENSE
-          to: .
-      bin: kyverno
     - selector:
         matchLabels:
           os: darwin