Chat reporting does not prevent dates from far into the future

PlayerChatMessage#hasExpiredServer and #hasExpiredClient are checking that the dates are not older than 5mins or 7mins respectively, however, nothing seems to be checking that they aren't far into the future, leaving potential for someone just saying they're typing 100 years into the future (as long as each of their messages keeps incrementing the timestamp a little).

While this is not gamebreaking it will probably create some weird-looking context in a report.