fix(comments): fix cactus comments

closes https://github.com/CaiJimmy/hugo-theme-stack/issues/470

data/external.yaml

@@ -41,7 +41,6 @@ Cactus:
     - src: https://latest.cactus.chat/cactus.js
       integrity:
       type: script
-      defer: false
     - src: https://latest.cactus.chat/style.css
       integrity:
       type: style

layouts/partials/comments/provider/cactus.html

@@ -1,5 +1,5 @@
 {{- with .Site.Params.comments.cactus -}}
-{{- partial "helper/external" (dict "Context" . "Namespace" "Cactus") -}}
+{{- partial "helper/external" (dict "Context" $ "Namespace" "Cactus") -}}
 
 <style>
     .cactus-editor-textarea {

layouts/partials/helper/external.html

@@ -8,7 +8,7 @@
                 integrity="{{ . }}"
                 {{- end -}}
                 crossorigin="anonymous"
-                defer="{{ default false .defer }}"
+                {{ if .defer }}defer{{ end }}
                 >
             </script>
         {{- else if eq .type "style" -}}