Fix links in text/plain posts not getting converted to HTML

lib/clacks/user_actions_helper.ex

@@ -118,7 +118,7 @@ defmodule Clacks.UserActionsHelper do
     {String.replace(content, ["\r\n", "\n"], "<br>"), mentions}
   end
 
-  @link_regex ~r/\bhttps?\S+\b/i
+  @link_regex ~r/\b(https?\S+)\b/i
 
   defp replace_links(content) do
     Regex.replace(@link_regex, content, "<a href=\"\\1\">\\1</a>")