minor: fix typo in error msg
minor: fix typo in error msg

yunstanford/sanic,ashleysommer/sanic,yunstanford/sanic,ashleysommer/sanic,yunstanford/sanic,yunstanford/sanic,channelcat/sanic,channelcat/sanic,channelcat/sanic,channelcat/sanic,ashleysommer/sanic