Small typo in comments of Media Type supported

Comment From: pivotal-cla

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Comment From: pivotal-cla

@pri88yank Thank you for signing the Contributor License Agreement!

Comment From: snicoll

@pri88yank thank you for making your first contribution to Spring Framework. I've found two more references to that typo and I've fixed that in https://github.com/spring-projects/spring-framework/commit/549f6c1e8007191ec627302524e9c4586efca587