fix(flat-pages): prevent appending redirect pages to the list

Author: danieIabel

layouts/partials/flat-pages.html

@@ -1,7 +1,12 @@
 {{- $pages := slice -}}
 
 {{- range (where .Section.Pages "Params.hidden" "ne" true) -}}
-  {{- $pages = $pages | append . -}}
+  {{- $isRedirect := or (isset .Params "redirect") (eq .Params.layout "redirect") -}}
+
+  {{- if not $isRedirect -}}
+    {{- $pages = $pages | append . -}}
+  {{- end -}}
+
   {{- if .IsSection -}}
     {{- $subPages := partial "flat-pages" (dict "Section" .) -}}
     {{- $pages = $pages | append $subPages -}}