Fix WithTestRegistry so that feature flags apply to the callback

[techanvil]

Feature Description

As discussed here, using WithTestRegistry while providing a callback alongside a set of features can lead to unexpected results, because the features won't be enabled until after the callback has executed.

This is illustrated with a contrived story in PR #10758, but as can be seen from the comment linked above it's something we've run into during active development.

We should ensure the features are enabled prior to the callback executing to reflect the real-world expectation of how features should be applied.

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Acceptance criteria

• Use of WithTestRegistry should be updated so that enabled features apply when executing the callback.

Implementation Brief

• Remove the features prop from WithTestRegistry and instead import enabledFeatures from tests/js/utils.js.
• Update all stories which pass the features prop to WithTestRegistry to intead provide them via {Story}.parameters.features, this will ensure enabledFeatures is updated via this default decorator in storybook/preview.js.

Test Coverage

• Ensure all stories are unchanged.
• No new tests needed.

QA Brief

Changelog entry

[nfmohit]

IB ✅