fix shortcodes rendering markdown img

replace markdownify with .Page.RenderString, the latter trigger render hook properly

see: https://gohugo.io/functions/markdownify/#readout
> Note: if you need Render Hooks, which markdownify doesn’t currently support, use .RenderString instead.

layouts/shortcodes/collapse.html

@@ -1,4 +1,4 @@
 <p><details {{ if (eq (.Get "openByDefault") true) }} open=true {{ end }}>
   <summary markdown="span">{{ .Get 0 | markdownify }}</summary>
-  {{ .Inner | markdownify }}
+  {{ .Page.RenderString .Inner }}
 </details></p>

layouts/shortcodes/figure-img.html

@@ -1,5 +1,5 @@
 <figure class="center align-center">
-  {{ .Inner | markdownify }}
+  {{ .Page.RenderString .Inner }}
 
   <figcaption><p>{{ .Get 0 | markdownify }}</p></figcaption>
 </figure>

layouts/shortcodes/image-size-control.html

@@ -2,5 +2,5 @@
 {{- with (.Get "width") }}max-width: {{ . }};{{ end -}}
 {{- with (.Get "height") }}max-height: {{ . }};{{ end -}}
 ">
-  {{ .Inner | markdownify }}
+  {{ .Page.RenderString .Inner }}
 </div>

layouts/shortcodes/standout.html

@@ -1,3 +1,3 @@
 <p class="standout">
-  {{ .Inner | markdownify }}
+  {{ .Page.RenderString .Inner }}
 </p>