`EXPIREAT`

Set a key's expiry as an absolute Unix timestamp in seconds.

语法	`EXPIREAT key unix-time-seconds`
分组	generic
参数个数	3
起始版本	1.0.0
标志	write
复杂度	O(1)
Redis 兼容性	differs: the NX / XX / GT / LT condition flags are not parsed — arity is fixed at 3