Explain why specifying ansible extra_arguments doesn't work same as normal ansible

[ghost]

This issue was originally opened by @timblaktu as hashicorp/packer#11086. It was migrated here as a result of the Packer plugin split. The original body of the issue is below.

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Here it tells users that they need to use an = between key/value in extra_arguments, but it's mysterious why until you look in one of the many past Packer issues related to this, e.g. here or here. I believe the latter link indicates that Packer is doing word splitting by whitespace before passing these to ansible, which is why the args are all wrong and the ansible call doesn't get off the ground.

I believe the description here should explain this, and also suggest that because the whitespace is the problem, users should also be mindful and take care to use quotes around entities containing whitespace."