Fix recursive dependency in image_diff

What does this MR do?

Breaks circular dependency in image_diff by introducing new helper

Before

  graph LR;
  image_diff/image_diff --> image_diff/helpers/index
  image_diff/helpers/index --> image_diff/helpers/utils_helper
  image_diff/helpers/utils_helper --> image_diff/replaced_image_diff;
  image_diff/replaced_image_diff --> image_diff/image_diff;

After

  graph LR;
  image_diff/image_diff --> image_diff/helpers/index
  image_diff/helpers/index --> image_diff/helpers/utils_helper
  image_diff/replaced_image_diff --> image_diff/image_diff;
  sq[image_diff/init_image_diff] --> image_diff/image_diff;
  image_diff/helpers/utils_helper -.-> image_diff/replaced_image_diff;
  sq[image_diff/init_image_diff] --> image_diff/replaced_image_diff;

  classDef orange fill:#f96
  class sq orange

We're using default export with object, instead of directly exporting function in order to be able to use mocking in tests, instead of rewiring

See #31702 (closed) for details

Does this MR meet the acceptance criteria?

Conformity

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