Move ingress shim config from --set to values.yaml

app/models/clusters/applications/cert_manager.rb

@@ -33,16 +33,10 @@ module Clusters
             rbac: cluster.platform_kubernetes_rbac?,
             chart: chart,
             files: files.merge!(cluster_issuer_file),
-            postinstall: post_install_script,
-            application_flags: install_command_flags
+            postinstall: post_install_script
           )
         end
 
-        def install_command_flags
-          ['--set', 'ingressShim.defaultIssuerName=letsencrypt-prod'] +
-            ['--set', 'ingressShim.defaultIssuerKind=ClusterIssuer']
-        end
-
         private
 
         def post_install_script

vendor/cert_manager/values.yaml

+# These options provide fully automated TLS.
+# See https://github.com/jetstack/cert-manager/blob/master/docs/reference/ingress-shim.rst#configuration
+ingressShim:
+  defaultIssuerKind: "ClusterIssuer"
+  defaultIssuerName: "letsencrypt-prod"