PLT-5900 Removed automatic configuration of SiteURL (#5952)

* Revert "PLT-5765 Passed SiteURL to SendNotifications (#5705)"

This reverts commit a8e68bd890.

* Removed automatic configuration of SiteURL

* Reverted unintentional config changes

* Updated help text

* Added link to docs in Site URL warning

* Fixed merge conflict

api/post.go

@@ -60,7 +60,7 @@ func createPost(c *Context, w http.ResponseWriter, r *http.Request) {
 		post.CreateAt = 0
 	}
 
-	rp, err := app.CreatePostAsUser(post, c.GetSiteURL())
+	rp, err := app.CreatePostAsUser(post)
 	if err != nil {
 		c.Err = err
 		return
@@ -344,7 +344,7 @@ func getPermalinkTmp(c *Context, w http.ResponseWriter, r *http.Request) {
 		}
 	}
 
-	if list, err := app.GetPermalinkPost(postId, c.Session.UserId, c.GetSiteURL()); err != nil {
+	if list, err := app.GetPermalinkPost(postId, c.Session.UserId); err != nil {
 		c.Err = err
 		return
 	} else if HandleEtag(list.Etag(), "Get Permalink TMP", w, r) {