cert-manager: upgrade from 1.12.17 to 1.17.4

Change-Id: Iea0d6eac22a57f9f1fc522e6abdd9359fbbd1415
diff --git a/charts/cert-manager/templates/poddisruptionbudget.yaml b/charts/cert-manager/templates/poddisruptionbudget.yaml
index dab75ce..ae71eed 100644
--- a/charts/cert-manager/templates/poddisruptionbudget.yaml
+++ b/charts/cert-manager/templates/poddisruptionbudget.yaml
@@ -17,10 +17,13 @@
       app.kubernetes.io/instance: {{ .Release.Name }}
       app.kubernetes.io/component: "controller"
 
-  {{- with .Values.podDisruptionBudget.minAvailable }}
-  minAvailable: {{ . }}
+  {{- if not (or (hasKey .Values.podDisruptionBudget "minAvailable") (hasKey .Values.podDisruptionBudget "maxUnavailable")) }}
+  minAvailable: 1 # Default value because minAvailable and maxUnavailable are not set
   {{- end }}
-  {{- with .Values.podDisruptionBudget.maxUnavailable }}
-  maxUnavailable: {{ . }}
+  {{- if hasKey .Values.podDisruptionBudget "minAvailable" }}
+  minAvailable: {{ .Values.podDisruptionBudget.minAvailable }}
+  {{- end }}
+  {{- if hasKey .Values.podDisruptionBudget "maxUnavailable" }}
+  maxUnavailable: {{ .Values.podDisruptionBudget.maxUnavailable }}
   {{- end }}
 {{- end }}