feat(pie-storybook): DSW-2593 improve logic for conditional rendering of stories

[siggerzz]

Describe your changes (can list changeset entries if preferable)

This PR aims to improve the logic for the conditional rendering of stories. Previously, only stories with the .test.stories.ts extension were rendered in the new Storybook Testing deployment.

With this PR, we've introduced test specific stories in pie-storybook/stories/testing as we look to migrate more of our tests to use Storybook for the testbed.

Component Variant Stories
A new createVariantStory has been introduced to replicate the functionality of the old WebComponentTestWrapper.

Storybook example here

// pie-chip.test.stories.ts
const sharedPropOptions = {
    disabled: [true, false],
    isSelected: [true, false],
    isLoading: [true, false],
    isDismissible: [true, false],
    showIcon: [true, false],
    slot: ['Hello World'],
};

const defaultPropOptions = {
    ...sharedPropOptions,
    variant: ['default'],
};

const ghostPropOptions = {
    ...sharedPropOptions,
    variant: ['ghost'],
};

const outlinePropOptions = {
    ...sharedPropOptions,
    variant: ['outline'],
};

export const DefaultPropVariations = createVariantStory<ChipProps>(Template, defaultPropOptions);
export const GhostPropVariations = createVariantStory<ChipProps>(Template, ghostPropOptions);
export const OutlinePropVariations = createVariantStory<ChipProps>(Template, outlinePropOptions);

@justeattakeaway/generator-pie-component

• Updated and tested generator to align with new testing process

Docs - https://github.com/justeattakeaway/pie/wiki/Testing-of-PIE-Components

Author Checklist (complete before requesting a review)

• I have performed a self-review of my code
• I have reviewed the PIE Storybook/PIE Docs PR preview

Reviewer checklists (complete before approving)

Reviewer 1 - @fernandofranca

• I have reviewed the PIE Storybook/PIE Docs PR preview

Reviewer 2 - @jamieomaguire

• I have reviewed the PIE Storybook/PIE Docs PR preview

[changeset-bot]

🦋 Changeset detected

Latest commit: ff40cf7

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@justeattakeaway/generator-pie-component	Minor

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[jamieomaguire]

All looks good, but please can you write up some documentation before merging? Basically how do we write stories and where, with this new approach and explain when and how to use each, I think.

[siggerzz]

All looks good, but please can you write up some documentation before merging? Basically how do we write stories and where, with this new approach and explain when and how to use each, I think.

As discussed, this has already be done, and will be improved futher at the end of this epic 👍🏼