fix for non existing atom

lib/pleroma/config/config_db.ex

@@ -236,15 +236,7 @@ def from_binary_with_convert(binary) do
   end
 
   @spec from_string(String.t()) :: atom() | no_return()
-  def from_string(":" <> entity), do: String.to_existing_atom(entity)
+  def from_string(string), do: do_transform_string(string)
-
-  def from_string(entity) when is_binary(entity) do
-    if is_module_name?(entity) do
-      String.to_existing_atom("Elixir.#{entity}")
-    else
-      entity
-    end
-  end
 
   @spec convert(any()) :: any()
   def convert(entity), do: do_convert(entity)

test/config/transfer_task_test.exs

@@ -105,17 +105,4 @@ test "transfer config values with full subkey update" do
       Application.put_env(:pleroma, :assets, assets)
     end)
   end
-
-  test "non existing atom" do
-    ConfigDB.create(%{
-      group: ":pleroma",
-      key: ":undefined_atom_key",
-      value: [live: 2, com: 3]
-    })
-
-    assert ExUnit.CaptureLog.capture_log(fn ->
-             TransferTask.start_link([])
-           end) =~
-             "updating env causes error, group: \":pleroma\" key: \":undefined_atom_key\" value: [live: 2, com: 3] error: %ArgumentError{message: \"argument error\"}"
-  end
 end