fix: invalid mutation for product media gallery

[joekendal]

On Version 2, the admin dashboard has an error

This PR fixes the following error on the product media gallery:

{type: "invalid_data",…}
message
: 
"Invalid request: Expected type: 'object' for field 'images, 0', got: 'string'"
type
: 
"invalid_data"

Steps to reproduce:

1. use the preview
2. navigate to a product with multiple images
3. don't click on edit. just click on an image
4. click on the trash icon
5. see error in terminal and browser console/network tab

[changeset-bot]

⚠️ No Changeset found

Latest commit: a9f5219

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[vercel]

@joekendal is attempting to deploy a commit to the medusajs Team on Vercel.

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[sradevski]

Thanks, we'll have it merged soon!