fix upstream header/nginx 502 bug by upping buffer

TemplateFiles/kuard-ingress.yaml

@@ -34,6 +34,11 @@ metadata:
   annotations:
     kubernetes.io/ingress.class: nginx
     cert-manager.io/cluster-issuer: letsencrypt-prod
+    nginx.ingress.kubernetes.io/proxy-buffering: "on"
+    nginx.ingress.kubernetes.io/proxy-buffers: "4"
+    nginx.ingress.kubernetes.io/proxy-buffers-number: "4"
+    nginx.ingress.kubernetes.io/proxy-buffer-size: "128k"
+    nginx.ingress.kubernetes.io/proxy-max-temp-file-size: "1024m"
 spec:
   rules:
   - host: {{APP_HOSTNAME}}