Remove accidental left-over content

Author: josevalim

lib/elixir/pages/references/compatibility-and-deprecations.md

@@ -231,20 +231,3 @@ Version | Deprecated feature                                  | Replaced by (ava
 [v1.17]: https://github.com/elixir-lang/elixir/blob/v1.17/CHANGELOG.md#4-hard-deprecations
 [v1.18]: https://github.com/elixir-lang/elixir/blob/v1.18/CHANGELOG.md#4-hard-deprecations
 [v1.19]: https://github.com/elixir-lang/elixir/blob/main/CHANGELOG.md#4-hard-deprecations
-
-#### Elixir
-
-  * [Code] The `on_undefined_variable: :warn` is deprecated. Relying on undefined variables becoming function calls will not be supported in the future
-
-  * [Kernel] Using `size(var)` in bitstrings requires the pin operator on the variable if the variable was defined outside of the current pattern
-  * [Kernel.ParallelCompiler] Passing `return_diagnostics: true` as an option is required on `compile`, `compile_to_path` and `require`
-
-#### Logger
-
-  * [Logger] `Logger.enable/1` is deprecated in favor of `Logger.delete_process_level/1`
-  * [Logger] The `:backends` configuration is deprecated, either set the `:default_handler` to false or start backends in your application start callback
-
-#### Mix
-
-  * [mix] The `:default_task`, `:preferred_cli_env`, and `:preferred_cli_target` configuration inside `def project` in your `mix.exs` has been deprecated in favor of `:default_task`, `:preferred_envs` and `:preferred_targets` inside the `def cli` function
-  * [mix do] Using commas as task separator in `mix do` (such as `mix do foo, bar`) is deprecated, use `+` instead (as in `mix do foo + bar`)