Fix typo on module attribute

Fix typo in @max_attempts in Dynamo.Templates.Renderer. 
Also, it seems causing the following warning at compile.

```
Compiled lib/dynamo/utils/message_verifier.ex
nofile:0:  undefined module attribute @max_attemps, please remove access to @max_attemps or explicitly set it to nil before access
Compiled lib/dynamo/utils/once.ex
nofile:0:  undefined module attribute @max_attemps, please remove access to @max_attemps or explicitly set it to nil before access
```

it's defined as
```
defmodule Dynamo.Templates.Renderer do
  @moduledoc false
  @slots 1_000_000
  @max_attempts 1_000
```