All double sided cards list their own unique id for other_face_unique_id

[pnelson5]

Version 6.7.0

Files impacted:
card.json
card-flattened.json

This appears to be an issue with all double-sided cards, though I didn't verify all of them.

Example:
Singularity // Teklovossen, the Mechropotent

card-face-association.json correctly lists a single entry as follows:

{
    "front_unique_id": "j8rcMLgRNcGQ6tqRpPhGT",
    "back_unique_id": "7NMRKm6kfknwgGWdmg8jB",
    "is_DFC": true
},

However, card.json and card-flattened.json both have printings for the back of the card with this:

Front face (Singularity):

{
    "unique_id": "j8rcMLgRNcGQ6tqRpPhGT",
    "set_printing_unique_id": "FrDDbdr69bML776RTLjTW",
    "id": "EVO010",
    ...
    "image_url": "https://storage.googleapis.com/fabmaster/cardfaces/2023-EVO/EN/EVO010.png",
    "tcgplayer_product_id": "518651",
    "tcgplayer_url": "https://www.tcgplayer.com/product/518651?Language=English&Printing=Normal",
    "double_sided_card_info": [
        {
            "other_face_unique_id": "7NMRKm6kfknwgGWdmg8jB",
            "is_front": true,
            "is_DFC": true
        }
    ]
}

Back face (Teklovossen, the Mechropotent):

{
    "unique_id": "7NMRKm6kfknwgGWdmg8jB",
    "set_printing_unique_id": "FrDDbdr69bML776RTLjTW",
    "id": "EVO010",
    ...
    "tcgplayer_product_id": "518651",
    "tcgplayer_url": "https://www.tcgplayer.com/product/518651?Language=English&Printing=Normal",
    "double_sided_card_info": [
        {
            "other_face_unique_id": "7NMRKm6kfknwgGWdmg8jB",
            "is_front": false,
            "is_DFC": true
        }
    ]
},

Notice the back face lists itself as the "other_face_unique_id" when I think it should be j8rcMLgRNcGQ6tqRpPhGT in this example.