Dont send ssl_support_method for default certificate

[rusowyler]

what

• Don't send ssl_support_method when using cloudfront_default_certificate

why

• It's only required if you specify acm_certificate_arn or iam_certificate_id
• Sending it will cause Terraform to try to update CF on every deploy

  ~ viewer_certificate {
      + ssl_support_method             = "sni-only"
        # (2 unchanged attributes hidden)
    }
    # (5 unchanged blocks hidden)

[Gowiem]

/test all

[Gowiem]

Thanks for the contribution @rusowyler! Released as 0.24.1.