Remove a redundant empty `RESTRICT_ON_SEND`
Remove a redundant empty `RESTRICT_ON_SEND`

Follow up to https://github.com/rubocop/rubocop/commit/cf96730

tejasbubane/rubocop,rrosenblum/rubocop,tejasbubane/rubocop,maxjacobson/rubocop,tejasbubane/rubocop,bbatsov/rubocop,maxjacobson/rubocop,rrosenblum/rubocop,rrosenblum/rubocop,maxjacobson/rubocop,bbatsov/rubocop