FIX: re-add mx_server_is_in?(domain_list) for backwards compatibility

[phoet]

@nijikon could you use this branch and check if that works as expected?

[nijikon]

@phoet I don't think we need to re-add it, but you decide. I would update the docs and include a note about the change in the CHANGELOG.

allow_any_instance_of(ValidEmail2::Address).to receive_messages(valid_mx?: true, valid_strict_mx?: true, disposable_mx_server?: false)

[phoet]

putting it back in place is the sensible thing to do. i would not touch the docs for now as it's likely going to change soon again.

[nijikon]

@phoet Sounds good. I can confirm that it works as expected with these changes.

[phoet]

great, i can test if our automated release workflow is back on track!