Adds v1beta1 as a supported admissionReviewVersion with a note as to

why it is listed even though we don't support it

Signed-off-by: joshvanl <vleeuwenjoshua@gmail.com>

deploy/charts/cert-manager/templates/webhook-mutating-webhook.yaml

@@ -26,7 +26,15 @@ webhooks:
           - UPDATE
         resources:
           - "*/*"
-    admissionReviewVersions: ["v1"]
+    # We don't actually support `v1beta1` but is listed here as it is a
+    # required value for
+    # [Kubernetes v1.16](https://github.com/kubernetes/kubernetes/issues/82025).
+    # The API server reads the supported versions in order, so _should always_
+    # attempt a `v1` request which is understood by the cert-manager webhook.
+    # Any `v1beta1` request will return an error and fail closed for that
+    # resource (the whole object request is rejected). When we no longer
+    # support v1.16 we can remove `v1beta1` from this list.
+    admissionReviewVersions: ["v1", "v1beta1"]
     # This webhook only accepts v1 cert-manager resources.
     # Equivalent matchPolicy ensures that non-v1 resource requests are sent to
     # this webhook (after the resources have been converted to v1).

deploy/charts/cert-manager/templates/webhook-validating-webhook.yaml

@@ -36,7 +36,15 @@ webhooks:
           - UPDATE
         resources:
           - "*/*"
-    admissionReviewVersions: ["v1"]
+    # We don't actually support `v1beta1` but is listed here as it is a
+    # required value for
+    # [Kubernetes v1.16](https://github.com/kubernetes/kubernetes/issues/82025).
+    # The API server reads the supported versions in order, so _should always_
+    # attempt a `v1` request which is understood by the cert-manager webhook.
+    # Any `v1beta1` request will return an error and fail closed for that
+    # resource (the whole object request is rejected). When we no longer
+    # support v1.16 we can remove `v1beta1` from this list.
+    admissionReviewVersions: ["v1", "v1beta1"]
     # This webhook only accepts v1 cert-manager resources.
     # Equivalent matchPolicy ensures that non-v1 resource requests are sent to
     # this webhook (after the resources have been converted to v1).