Remove unused ets function from adapter

Author: apata

lib/plausible/cache/adapter.ex

@@ -64,10 +64,6 @@ defmodule Plausible.Cache.Adapter do
       nil
   end
 
-  def ets(cache_name) do
-    ConCache.ets(cache_name)
-  end
-
   @spec get(atom(), any(), (-> any())) :: any()
   def get(cache_name, key, fallback_fn) do
     full_cache_name = get_name(cache_name, key)