There aren't any built-in tools for this. There are several third-party applications like Duplicate Annihilator, but they don't always work 100%, and have damaged the Photos Library on occasion. I haven't ever used them personally, so I don't have any recommendation other than manually managing your photos.
If you want to delete duplicate photos quickly then use the 30-days free trial of Speedup Mac. It is a free tool to remove redundant files in one click.
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