Move js dependencies required for backstop tests into their own workspace

[eugene-manuilov]

Feature Description

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Do not alter or remove anything below. The following sections will be managed by moderators only.

Acceptance criteria

• The package.json file is updated to have tests/backstop in the workspaces array.
• JavaScript dependencies that are needed for backstop to function properly are moved to the new workspace.
• GitHub actions for vrt are updated accordingly to continue running for all PRs.

Implementation Brief

• Update package.json, adding a new workspace "tests/backstop".
• Create a new package.json file in tests/backstop folder using npm init -w ./tests/backstop.
  • Copy the scripts for backstop tests but not for building storybook to this new package.json:
    • test:visualtest
    • test:visualapprove
    • backstopjs
      Fix any paths and ensure the commands work correctly after the refactor.
• Scan all dependencies that we have in the main package.json file and move all dependencies that are used in backstop tests to its own package by uninstalling them in the main package.json file and installing with -w ./tests/backstop argument to specify the correct workspace.
• Update the package.json file to proxy backstop commands to the correct workspace using the npm run ... -w ./tests/backstop approach.

Test Coverage

• N/A

QA Brief

Changelog entry

[techanvil]

IB ✅