FEATURE: unhide the embed_whitelist_selector setting (#7137)

* Unhide embed_whitelist_selector Site Setting and move it to Posting section
* Add i18n key for the embed_whitelist_selector setting

config/locales/server.en.yml

@@ -1876,6 +1876,7 @@ en:
 
     embed_truncate: "Truncate the embedded posts."
     embed_support_markdown: "Support Markdown formatting for embedded posts."
+    embed_whitelist_selector: "A comma separated list of CSS elements that are allowed in embeds."
     allowed_href_schemes: "Schemes allowed in links in addition to http and https."
     embed_post_limit: "Maximum number of posts to embed."
     embed_username_required: "The username for topic creation is required."

config/site_settings.yml

@@ -790,6 +790,8 @@ posting:
     default: true
   embed_support_markdown:
     default: false
+  embed_whitelist_selector:
+    default: ""
   allowed_href_schemes:
     client: true
     default: ""
@@ -1473,9 +1475,6 @@ embedding:
   embed_title_scrubber:
     default: ""
     hidden: true
-  embed_whitelist_selector:
-    default: ""
-    hidden: true
   embed_blacklist_selector:
     default: ""
     hidden: true