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

• [-] Changelog entry for user-facing changes, or community contribution. Check the link for other scenarios.
• [-] Documentation created/updated or follow-up review issue created
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• [-] Separation of EE specific content

changed milestone to %12.3

added backstage [DEPRECATED] test workflowin dev labels

mentioned in merge request gitlab-foss!32831 (closed)

mentioned in issue #31702 (closed)

mentioned in merge request gitlab-foss!32869 (closed)

	1 Warning
	This merge request changed files with disabled eslint rules. Please consider fixing them.

Disabled eslint rules

The following files have disabled eslint rules. Please consider fixing them:

• app/assets/javascripts/single_file_diff.js

Run the following command for more details

node_modules/.bin/eslint --report-unused-disable-directives --no-inline-config \
  'app/assets/javascripts/single_file_diff.js'

Reviewer roulette

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Category	Reviewer	Maintainer
frontend	Adriel Santiago (@adrielsantiago)	Clement Ho (@ClemMakesApps)

Generated by Danger

changed the description

changed milestone to %12.4

Hi, @ClemMakesApps, could you please make a maintainer review Reviewer approval granted at gitlab-foss!32869 (comment 216669403)

added workflowin review label and removed workflowin dev label

assigned to @ClemMakesApps

LGTM. Thanks for the detailed diagram

changed milestone to %12.3

approved this merge request

merged

mentioned in commit 24ed1470