USH-1683 - Posts not submitting for surveys with the old image field

[ushahidlee]

Issue:

For surveys with the previous image field, posts fail to submit if an image is not uploaded.

Solution:

A tiny little fix that presents an empty array, rather than a null value in the field values.

Ticket:

https://linear.app/ushahidi/issue/USH-1683/posts-not-submitting-for-surveys-that-already-had-image-field#comment-03592f34

Testing:

1. Create a survey with an old image field.
2. Create a new post of the above survey, but without uploading an image.
3. Submit the post successfully.

[linear]

USH-1683 Posts not submitting for surveys that already had image field

[Angamanga]

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